o, if you're really really that worried about your credit rating instead of ENACTING SWEET REVENGE on the person who mixed up your cards, you should have your lawyer look over your credit policies and see what he can do, because, shit, if you've got a frickin' lawyer in your family's pocket, I'm pretty sure you're not stupid enough to sign up for a card that offers absolutely zero theft protection. And it sounds like that's what you're getting. I'd look into that.
Also, how long did you wait to cancel your card after you found out? Because where the FUCK do you find a $10,000 dollar stock television, let alone one where you can walk in, buy one, and leave, all between the amount of time it took for you to pick up your phone and cancel your card.