I don't know why he does not appear at all in the roster of the 192nd. However, the 1890 special veterans census lists him as serving in that unit from Feb 9, 1865 to Aug 24, 1865. Also he and his widow Celia received a pension for his service, but they are listed under the name Groves. The National Archives in Washington, DC would have his pension record.
In case you're interested his Pennsylvania death certificate lists his birth date as Jan 5, 1841 and death date as July 4, 1914. His parents are listed as John Grove and Elizabeth Walters.