Roster of Confederate Soldiers, 1861-1865, shows:

Gardner, William KY 10th (Johnson's) Cav. Co.D 2nd Lt.
Gardner, William KY 1st (Butler's) Cav. Co.F
Gardner, William KY Cav. 2nd Bn. (Dortch's) Co.C 2nd Lt.

Roster of Union Soldiers, 1861-1865, shows:

Gardner, William KY 24th Inf. Co.F
Gardner, William KY 48th Inf. Co.H