Based on the fact that he’s the only Joshua ULLOM?OLLOM in the file and the age is right, as well.

Joshua Ollom (probably a misspelled Ullom):
Enlisted 28 January 1865 as a Private at the age of 29.
Served Ohio, Enlisted F Co. 187th Inf Reg. OH Mustered Out at Macon, GA on 20 January 1866
Source: Official Roster of the Soldiers of the State of Ohio, Published by Wilstach, Baldwin, in 1886