I have a C.M. Walker, Company A, 27th Texas Cavalry Regiment who mustered at Daingerfield, TX 10 Mar 1862. Detached service most of 1862 driving a wagon. Present in December. Lost his musket in June 1863. Detached service with QM Department as teamster for rest of war. Being available in December would have allowed him to go on the Holly Springs Raid. If he died in the war it was on the way home. I see no listing of parole.
There were also a D.M., J.E.W., and a John C. Walker, in A Company. This could be your man.