The failures of June 16 would be blamed on Ney.  He would soon find company.

Soult would immortalize the complaints against Ney in #26 of the Registre du major-général, with the original also found in Archives Nationales, Pierrefitte-sur-Seine, Papiers du maréchal Ney, 137 AP/18.  Ney did not keep his forces together, which still appears to be the fault of Soult, and failed to occupy Quatre-Bras.  In this case, there are missing reports and correspondence that could greatly illuminate the events, including pieces that have been sold at auction in the last 20 years.

In the morning, Napoleon toured the Ligny battlefield while Soult remained in Fleurus.  The discovery of Soult’s Mouvement des Troupes, Enrégistrement de la correspondance, commencée le 11 Mai 1815, Collection Francois Gianadda, Martigny, provides the missing detail of Soult’s activities in Fleurus during the morning of June 17, as delineated below:

#361 to Langeron – Movement of National Guards Battalion
#362 to Daure –  Sent utensils for 5,000 men to Lillie
#363 to Commandant Avesnes – Forward detachments coming from Paris to the army by Beaumont and Charleroi
#364 to Reille, Lobau, Ruty & Gérard – Notice of above arrival of detachments.
#365 to Commandant Avesnes – Unite columns of march, formed from deserters and crews furnished by other departments.
#366 to Général Frère – Napoleon ordered 10 battalions of National Guards to be stationed at Avesnes
#367 to Commandant Avesnes – Notice of National Guard battalions intended to escort prisoners
#368 to Ruty – Order to replace the daily consumption of ammunition
#369 to Lieutenant Général Lebel, Measures to ensure order and tranquility of the houses where the headquarters will go.

There is only one additional letter listed in the Registre du major-général, which is curious considering the Army was about to be split in two and be sent on pursuit of both allied Armies.  Soult also sent a letter to Davout announcing the victory at Ligny.

Napoleon gave Grouchy verbal orders in the late morning to begin organizing a force to pursue the Prussians, but after Grouchy rode off, he would adjust it.  As Soult had not come from Fleurus, it was Bertrand who acted in his place:

ordre au Mal Grouchy.

Ordonnez au Gal Domon de se rendre sur le champ à Marbais. Il y sera sous les ordres du Comte de Lobau. il dirigera de détachements sur les 4 chemins, route de Bruxelles, et se réunira par la gauche avec les troupes des 1er et 2e Corps, qui occupent ce matin le village de Frasne et qui doivent aussi marcher sur les 4 chemins, où les Anglais sont supposés être. Ordonnez au Gal Milhaud de se rendre à Marbais. Il aura devant lui la cavalerie légère du Gal Domon. il y trouvera le corps du Cte de Lobau et la Garde. Ligny ce 17 Juin.

Dicté par l’Empereur en l’absence
du Maj Gal L G. Mal
Bertrand

Archives Nationales, Pierrefitte-sur-Seine, Dossier 3 : Lettres du maréchal Soult à sa femme and Dossier 5 : Pièces diverses, 699 Mi

Translated:

Order General Domon to go to Marbais immediately. He will be there under the orders of Count Lobau. He will direct detachments to the Quatre Bras, Brussels road, and will assemble by the left with the troops of the 1st and 2nd Corps, that this morning occupy the village of Frasne and who must also go to the Quatre Bras where the English are supposed to be. Order General Milhaud to go to Marbais. He will have before him General Domon’s Light Cavalry. He will find Count Lobau’s Corps and Guard there.

With Soult still absent, Napoleon finalized pursuit orders, thus beginning Grouchy’s long Waterloo nightmare.  These orders are provided as a copy in the archives:

17 Juin 1815.
Ordre de l’Empereur. (au M Grouchy.)
Rendez-vous à Gembloux avec le Corps de cavalerie du Gal Pajol, la cavalerie légère du 4e Corps, le corps de cavalerie du Général Exelmans, la division du Gal Teste, dont vous aurez un soin particulier, étant détachée de son Corps d’armée, et les 3e et 4e Corps d’infanterie. Vous vous ferez éclairer sur la direction de Namur et de Maëstricht, et vous poursuivrez l’ennemi. Éclairez sa marche et instruisez-moi de ses mouvements, de manière que je puisse pénétrer ce qu’il veut faire. Je porte mon quartier général au Quatre Chemins, où ce matin étaient encore les Anglais. Notre communication sera donc direct par la route pavée de Namur. Si l’ennemi à évacué Namur, écrivez au Général commandant la 2e division militaire à Charlemont de faire occuper Namur par quelques bataillons de gardes nationales et une batterie des canons qu’il formera à Charlemont. Il donnera ce commandement à un maréchal de camp.
Il est important important de pénétrer ce que l’ennemi veut faire. Ou il se sépare des Anglais, ou ils veulent se réunir encore pour couvrir Bruxelles et Liège, en tentant le sort d’une nouvelle bataille. Dans tous les cas, tenez constamment vos deux corps d’infanterie réunis dans une lieue de terrain et occupez tous les soirs une bonne position militaire, ayant plusieurs débouchés de retraite. Placez des détachements et cavalerie intermédiaire pour communiquer avec le quartier général.

Ligny, le 17 Juin 1815.
Dicté par l’Empereur en l’absence du Major général.
Le Grand Maréchal
(Signé) Bertrand.
P.C.C. à l’original communiqué
par le Comdt du Casse en Juin 1865.
Le commis chargé du travail :
D. Huguenin

Translated:

Go to Gembloux with General Pajol’s Cavalry Corps, the Light Cavalry of the 4th Corps, General Exelmans’ Cavalry Corps, General Teste’s Division , because it is detached from its Army Corps, pay particular attention to it, and the 3rd and 4th Infantry Corps. You will scout in the direction of Namur and Maestricht, and you will pursue the enemy. Scout his march and inform me of his movements so that I can perceive what he will do.
I bring my headquarters to the Quatre Bras where the English remained this morning. Our communication will therefore be direct, along the paved Namur road. If the enemy has evacuated Namur, write to the commanding General of the 2nd Military Division at Charlemont to occupy Namur with some National Guard battalions and a battery of artillery which he will form in Charlemont. He will give this command to a Maréchal de Camp.
It is important to perceive what the enemy wants to do. Either it separates from the English, or they want to assemble again to cover Brussels and Liege, while tempting fate with a new battle. In any case, always keep your two Infantry Corps gathered together in one league of ground and every evening occupy a good military position, having several debouches for retreat. Position detachments of intermediary cavalry to communicate with the headquarters.

Grouchy would deny the existence of the above order. In Pierart’s Drame de Waterloo, a footnote on pages 238-239 identifies that the order was published by the printer Bauduin in Paris, and that the order is dated at 3:00pm. Interesting to see this order printed in the year Napoleon’s remains returned to France.  The late time given would be favorable to Grouchy as his pursuit was considered late and less than inspired  The order was also revealed in a biography of Grouchy, Notice Biographique sur le Marechal de Grouchy published in 1842.  Grouchy may have inadvertently included the order in his papers he made available, considering how long he had denied anything like it existed.

Around midday, after Soult rejoined Napoleon, the following orders were sent to Ney.  This was not recorded in either registry:

en avant de Ligny le 17 juin,à midi.

Monsieur le Maréchal l’Empereur vient de faire prendre position en avant de Marbais à un corps d’infanterie et à la garde impériale; S. M. me charge de vous dire que son intention est que vous attaquiez les ennemis aux 4 Bras, pour les chasser de leur position, et que le corps qui est à Marbais secondera vos opérations, S. M. va se rendre à Marbais et elle attend vos rapports avec impatience.

Le maréchal d’Empire, Major Général
duc de dalmatie

Archives Nationales, Pierrefitte-sur-Seine, Papiers du maréchal Ney, 137 AP/18.

Translated:

Marshal, the Emperor has just taken a position in front of Marbais, with a corps of Infantry and the Imperial Guard; H.M. desires me to tell you that his intention is that you attack the enemies at Quatre Bras, to drive them out of their position, and that the corps that is in Marbais will assist your operations; H.M. will go to Marbais, and waits impatiently for your reports.

David Chandler published an order, written at 1pm, that Napoleon sent himself urging Ney to action, in Waterloo, the Hundred Days, page 89.  Pierre de Wit offers a convincing argument that this order was sent on June 17:

Monsieur le prince de la Moskowa,
Je suis surpris de votre grande retard à exécuter mes ordres. Il n’y a plus de tems à perdre; attaquez avec le plus grande impétuosité tout ce que est devant vous. Le sort de la patrie est dans vos mains.
1 heure après midi
Napoleon

Original orders not in a registry is not uncommon.  What makes the analysis of the Registry d’ordre et de correspondance du major-général challenging is that the original is lost.  What survives is a hand-written copy in the Bibliothèque nationale de France, Paris, NAF 4366:

And later, Grouchy published this copy in his Relation Succincte de la campagne de 1815 en Belgique, published in 1843.

Grouchy would take possession of the Registry when he took command of the Army after the defeat.  Considering the missing orders and Grouchy’s actions, finding the original register used during combat operations would be very useful.