That Charlie Persip ad is proof enough for me. Gretsch would have hired the photographer and the ad agency. They would not have done all this and let someone bring in a set they had stripped the wrap off of. If anything they probably did these photo shoots when an artist was picking up a shiny new set of drums rather than having them bring in their gigging sets which might show some wear and tear.
Gretsch was known to be pretty cheap with their endorsers, generally only giving them one set at a time and taking the previous one back from them.
As to where these drums might be today that's anyone's guess. Maybe tucked away in an attic somewhere still waiting to be found by anyone who understands their significance. Or maybe Gretsch took them back from the artist and, since they weren't a cataloged finish, either destroyed them or wrapped them and shipped them out as new. I doubt we'll ever know. I'd sure like to find them though...