Took the X5 in for service today because of a strong vibration in the steering wheel when braking at a high or moderate speed. I suspected warped rotors. We got a call from the Service Advisor (left a message) said the tech said the brakes and suspension 'checked out fine' and the fix is to rotate and balance the tires.

I tried calling back and got the SAs voice mail, so instead I called the service manager. I explained the situation and he agreed that rotating and balancing the tires would probably not resolve anything and he would go talk to the tech and call back.
About an hour later the SA left another message saying that she talked to the service manager and they can't do anything more until they rotate and balance the tires at a cost of $88.

But they said if this doesn't resolve the problem they won't charge us for the work. I tell my wife to left them do it, and I was fairly certain it wouldn't make a difference. Sure enough, a few hours later they told us that it didn't fix the problem and they were going to have to keep the car overnight. So my wife is driving a '04 325 'loaner' that reeks of stale cigarette smoke and an awful tropical air freshener.
Our 3series said not to rotate the tires, but I cannot find any detail on a recommendation on the X5 (yes/no interval, etc.). What do you guys do? We have a little over 8k and it is just turned a birthday.
Any one else had vibration under braking? If so what was the root cause?
thanks.
-Jeff