Your hypothetical doesn't match reality. The accounts were linked through more than just the CC, and the CC wasn't stolen anyway (presumably Kapeli didn't chang

Your hypothetical doesn't match reality. The accounts were linked through more than just the CC, and the CC wasn't stolen anyway (presumably Kapeli didn't change the CC on his account, and the charge for the new account was never contested). And there's probably more than just the CC and test devices anyway, Apple probably used things like detecting that a computer used with one account was used to create the other, or the creator of the second account was currently logged in using the apple ID of the first, or something like that (but they probably don't go into detail about this because they don't want to tell fraudsters how to avoid detection).