He was carried on Company H books through February, 1864 as absent. There are no further muster rolls for the Company. Thus, it looks like he never returned to the regiment.
Here is a Yankee prisoner report which could possibly be your man:
Proceedings of a Military Commission: In the case of Thomas Renick, Citizen of Johnson Co. Mo.
Charge - Violation of Oath of Allegiance
Sentence - To be confined in a Military Prison at hard labor until the close of the present Rebellion
Approved Jefferson City, Mo. December 14, 1863
U.S., Union Provost Marshals' Papers, 1861-1867 for Thomas Renick
Citizen Prisoners Received at Military Prison, Alton, Illinois May 11, 1864
Thomas Renick of Johnson County, Mo., taken in Lafayette County, Mo.
November 1, 1863, discharged February 15, 1865
U.S., Civil War Prisoner of War Records