My wife received over a thousand dollars in mystery credit card charges from the App Store over a period of about 6 weeks. Apple couldn't explain it or provide

My wife received over a thousand dollars in mystery credit card charges from the App Store over a period of about 6 weeks. Apple couldn't explain it or provide any insight whatsoever. Nothing. Apparently, the charges were on her credit card but associated with another Apple ID. We did a charge back which was successful. Now, I'm just waiting for the inevitable locking of her Apple ID. Luckily, she has already created a new one, but if the same thing happened to me I'd be in serious trouble. In my case, simply creating a new Apple ID is not an option. It's really scary.