Maybe Nadal did use this at Wimbledon. He probably felt that using his real racquet wouldn't be fair to Roger after what happened at the French, so he went to the store to by some APDC's strung with stock strings. He left the dampener off to further level the playing field between himself and Roger. His hubris almost got the better of him, but in the end his talent prevailed. Notice how the strings on this racquet aren't worn at all - almost like they've never been used. That shows how easy Rafa was taking it on Roger.
So go ahead and make a bid to win that racquet. Rest assured that it's the genuine article and not just some cheap piece of crap with his signature on it.