Carrier/rack problems of the 2011 Volkswagen Touareg

While driving at approximately 60mph on a smooth two lane wide highway the front sunroof panel (panoramic) shattered. There were no other vehicles on the road, no overpasses and no trees above. It was around 65-70 degrees fahrenheit. It was not hailing or raining at the time. No objects were recovered from inside of the vehicle. The glass appeared to have broken upwards instead of inwards. Fiancé and two dogs (trunk area) were inside of the crucible. Glass caused very minor cuts. Vehicle recently detailed and also cleaned by myself. No rock chips present in sunroof glass. No visible cracks prior to incident.