It won't be all icing on the cake for Donald. He needs to prove he belongs in the top 40, which means he has to do a lot better than beating Gong or Soeda or players like them.
I think he'll be in the Top 40 in the next rankings win or lose.
This to me is exactly like the US Open Murray rematch, except that he beat Stan in a slam unlike 'only' IW for Murray. GS wins over a player carry much more weight than Masters wins so using that logic a Wawa win here won't kill Don's confidence unless it's a lopsided score