If you're like me and had your valid registration code applied to a previously unknown "maintenance account" while your real account with your characters is now locked, here's a way to get around it without waiting for SE.
1. Contact credit card company original purchase was made and dispute the charge as fraudulent. At no point in the transaction did SE state you would be buying a product through Digital River. Vast majority of people, if that was known, would have hit CANCEL and sought out a reputable merchant. Since SE arbitrarily assigned your code to an unused account, you have not received any good/services. It's a valid dispute.
2. Calla round and find a physical copy of the game. Found one near me at 3rd place I called.
3. Buy physical copy and enter registration code at that funky MOG site, not through regular registration process.
4. Login and play game.
You fix your problem and get the satisfaction of sticking DRI and SE with handling a dispute.