Hello. It is very possible that the book Rebel's Hell which is about the Union prison in Little Rock will have the information. All of the info in
the book came from the National Archives. If you are interested in the book, try for an interlibrary loan.
I suggest that because more than likely they were taken to Little Rock before being shipped north. That was what the book indicated when I was using it several years back.
My ancestor was picked up around Augusta in Nov. of 1864. I found by reaserching within that book all the names of the guys captured with him and what became of each including date of death, what killed them or when they took the oath as the war ended. All of the men that were picked up with my ancestor stayed right there in Little Rock and never shipped out though I saw plenty of names that did.
Linda