My WTF'ing was related to your buying a car and realizing it's a structural disaster two days later. It was partially in jest. All joking aside, glad you got your $ back. Two pieces of honest advice.
1. Start looking for a used X5 from a BMW dealer. Preferably a CPO. Yes you can buy a 70,000 X5 that is CPO. Not typically someone's first choice, but if you like the car and that's your budget, then at least you have some assurance the mess you experience once won't likely happen again from a BMW dealer on an inspected and 'certified' car.
2. Doesn't carfax have a guarantee of some sort. If I were you I'd get everything documented and start having my attorney call carfax ASAP. Their info has long been known to be sh_t at times and looks like it almost cost you a bundle. Not good.