It is possible, although the Roster doesn't list him as being there. As Hugh said, we need someone who is familiar with the 15th AR Inf and its records.

Have you tried the Arkansas History Commission, One Capitol Mall, Little Rock, AR 72201 gen info 501-682-6900 ? They are supposed to have: State Pension applications, Ex-Confederate amnesty papers, AR Confederate Home resident records, 1911-1912 Census of Confederate veterans living in AR, Registry of Confederate soldiers, sailors and citizens who died in federal prisons, etc.