Benjamin Franklin Giles is listed in the 5th South Carolina Infantry Regiment Company D. In July 1862, he supplied Peter Byers as a substitute and then was named Regimental Musician - a most unusual situation. The service record for Peter Byers states that he was detailed as wagon master, was wounded at Fussell's Mill and served out the remainder of the war as a hospital orderly.
I'm speculating that Benjamin was relieved of his duty as wagon-master on the condition he find a substitute i.e. Peter Byers. In most cases when a man obtained as substitute, it was to avoid personal duty, but such does not appear to be the case here.
Also listed in the same company are Joseph G. Giles and Thomas W. Giles.