Any reported instances of Vue sunroof detaching while driving.

Hello, this does sound terrifying and i'm so sorry it happened to you. I do not see any instances of recall for this via the recall database, nor are there technical service bulletins published for this concern. I also reviewed "common problems" here on RepairPal, and cannot find anyone who has shared the same concern. I'd recommend a body shop have a look at your vehicle to see what caused the failure, and then obviously get a quote for repairing it. You may want to contact your insurance company due to the unusual nature of this concern and see if comprehensive coverage may help repair this (if you have it). Good luck!