Even if the gold is cheap, there is quite a bit of demand. If the players duped a lot of gold they could still sell $250 worth... even if they had to sell a billion gold to do so. Considering that many of these 415 players probably did this, you can easily imagine that they tried to cash out up too $100,000. It probably was no where that high, but it could easily be around $10,000, which would be enough to make a significant donation, while not hurting Blizz's bottom line too much.
0