Quoted from hocuslocus:
I don't think GRG is doing that deal anymore, got one from them and like a week later the price was back at msrp.
As I mentioned earlier it’s a timing thing. When they are near ordering the next required batch of X games to acquire the limited platinum and diamond games they typically burn them out at wholesale. You are correct though, weeks after I got my game they shot back up to 8k.