Not sure why this didn't post the first time:

I'm sure that this document was misfiled, and should not be in this man's CMSR. A.M. stands for Army of Mississippi. This first incarnation of a unit by that name was commanded by Albert Sydney Johnston until he was killed in action at Shiloh, and the 1st Corps was commanded by Leonidas Polk. Cheatham commanded the 2nd division in that corps. That is the division and corps shown on the document. Your man, in the 9th Mississippi, was not in the 2nd Division, 1st Corps, but was in the 2nd Division (under Withers) of the 2nd Corps (under Bragg). It would take some digging to find out who this officer is, but it is pretty certain that it is not Private John M. Wahl.