I post this info just in case, but it really doesn't look like this was your soldier. Just the same name.
Pvt. James Johnson, Co. A, 1st Georgia Infantry, died 9 Jan. 1865 in one of the military prison hospitals in Louisville, and was buried in Grave 1R62 in what is now the Cave Hill National Cemetery in Louisville.
The Confederate POWs who died in 1865 were buried behind the Federal graves in what is now the Cave Hill Natl Cem, because the lots set aside for Confederate burials were then full. Johnson was the first such Confederate POW who had no room among the Confederates but had to be buried behind the Yankees. He was later joined by 37 Southern comrades who were buried there between Jan. and mid-June 1865. In the 1890s, burials of Union veterans filled in around these 38 Confederates, so that they are now surrounded by Yankees.