Nope. I think it was just a bluff to prevent any others from attempting to do it before they fixed it. You know, for damage control purposes and so those that didn't get the chance to do it aren't upset and will be appeased since they really believe Treyarch is doing something about it.
Anyone that did it should be good, no way you can get caught unless people are constantly reporting you when they see that you're max prestiged and your kills don't add up. Even then, I doubt they're going to act on a single report notice on your account, in the midst of the millions of other reports they have to sift through. So unless your account is popping up on multiple reports then I doubt anyone that did it has anything to worry about.