Hello. Without trying to be unkind to you, I believe you are using today's standards to try and understand something from the past.
I had several relatives from that time period who died while in the hands of the Yankees. I can assure you that the bodies were treated as well as the prisoners were and that was rather badly.
My ggg grandfather died of smallpox in the Yankee prison in Little Rock. The health authorities would not let the family have the body because of the serious nature of the disease.
My own gg grandfather walked home to central Arkansas from Texas and the family already believed him dead.
He died a few months later, but at least he made it home.
My ggg grandmother had three brothers with the 10th Arkansas by the name of Guthrie. One, Fielding, lived and went home. The baby brother, Owen, was shot at Shiloh and was evacuated being one of the thousands that waited to die and the last one, Frederick was captured down around Natchez dying in a Yankee Prison up in Indiana. This is not all of them but enough to give you an idea of what I am speaking of.
So while I have not really answered the question, what I have told you is true.
I do appreciate your desire to learn and I do encourage you to continue you search.