The only "YOUNG" I find in the 44th Tn Inf is a Pleasant F. Young, Pvt, Co H.
You've said that the William F. Young, Col in the 49th TN Inf is not the one you are after. The only other one that has the initils W.F.Young was listed in Bailey's Consolidated Regt, TN Inf, of which I have no information.
There are another 24 William Young's listed; none in the 44th Tn Inf.
JR