John O. Brister's compiled service record says he did in fact die in Atlanta July 14/19th(My copy is blurred) from wounds received at New Hope Church (May 25th-31st). The other mention of him states "died from wounds Atlanta works on Chattahoochee" with a note that says see "John Buster". We are now after John Buster's records. Believe that an assumption was made that he died soon after his wounds and that would mean he received them in the works. Once we see Buster's records, this should all be cleared up. The next mystery is whether J. Milton Brister's first name is James or John...I'm betting on John. Waiting for civil records, census, etc.
I have only seen one abstract of his records that identifies him as "Jas. Milton Brister. Everywhere else he is J. M. Brister or J. Milton Brister. No signatures other than J. M. Brister either. 50+ documents.