The soldier in my post enlisted in Alabama. His service records do not indicate where he was born and I've been unable to locate this man in Mississippi census records which is why I suggested a post on the Alabama Board for more info on this particular soldier.

"Can you tell if he ever drew a pension? My thought being the pension
would tell who Matthew R. Baynes actually served with."

I agree a pension record or application would be a big help, but I do not have access to these records.