Here is the Marietta National Cemetary site that lists him:
http://www.interment.net/data/us/ga/cobb/marienat/index_k.htm

Sounds like he died and was buried in Spaulding County and was dug up and moved to Marietta after the war. I know I have read stories about the U.S. Government offering money to people who would bring in the remains of Yankee soldiers to Marietta for burial. Some scam artists brought in animal bones just to collect the money so which grave he is really buried in would be a toss up.