2004 X5 4.4 front differential question

[h2oskiphil]

I had the front right CV axle replaced a couple of weeks ago, and last weekend, the X started making a weird noise after a couple hundred miles of driving. I thought it was coming from the right rear, but when my wife took it to the closest dealer (I was in a meeting and couldn't be there, which sucked), they drove it and started looking at the right front. They told my wife that the CV axle may have slipped out of the front diff when I made a hard RH turn, which they thought was causing the issue. They were getting ready to close and didn't have time to take it apart and verify, but they told her (and showed her) that when they rotated the RF wheel, the LF wheel didn't turn along with it. They also pointed out that a flange on the CV axle inboard of the inner CV joint wasn't flush against the differential.

I ended up trailering the X home the next day, and drove it for a couple of days with no noises whatsoever. I talked to the shop that installed the CV axle, and they told me that when they installed the axle, they got it in as deep as they could, and that the flange was not flush to the diff when everything was lined up. Obviously, once everything is tightened up, there's no place for that axle to go, and I drove it for several weeks before this trip with no issues whatsoever, and none since the trip.

Thoughts on this? Are the front wheels supposed to rotate in unison when one of them is turned? I'm leaving town tomorrow early AM, and I'm a little hesitant to take it, even though I've had no issues with it since I got it back home.