A.&R. mention that the Russian divisions were grouped in corps sometime in the prior days. Unfortunately they don’t specify what they were, but it seems clear the 5th and 8th formed a corps under Tuchkov, at least nominally. Not sure how it worked in practise.
Fock was an adjutant, so it seems reasonable that he would be put in charge of the 5th division once Tuchkov was promoted. Vasilyev has him subordinate to Rezvyy, but I will have to more carefully translate [i.e. not just drop it in Google] the St George commendation – it may indicate he was in charge of infantry and not the battery.
I applied my own guesses to the 3d Div as neither A.&R. nor V. are convincing.
Sukin-2 taking charge of the 2d division is perfectly plausible although neither A.&r. nor V. suggest it. Can you dig up any data?
Same for Zapolsky and the 7th?
Sievers was chief of the 5th Artillery Brigade, but Kutaisov was definitely at the battle and would have outranked him. If Fock is not commanding the center battery, then Loewenstern would most likely be there. Stavitsky was chief of the 2d Artillery Brigade and would likely be second to Rezvyy if present. But would he rather run around with his horse company?
I have Pahlen-3 on the right. I notice I forgot to mention my conventions – italic when officers are formally located but not physically present and ()’s where they are taking additional responsibilities.