It looks like, either Zolan McCarty or his Grandson, Chris English's work. Although neither did a great deal of Damascus, the blade, thumb screw and, particularly, the handle shape looks like theirs.
Hope this helps, Capt. Chris
PS: Tons of Chris' work had a simple capital "Z" engraved on the finished piece as a tribute and homage to his Grandad...CCS
PPS: One of Chris' autos in Oosic.!