Hatchback/liftgate Lock problems of the 2003 GMC Yukon

The contact owns a 2003 GMC Yukon. The contact stated that the tail gate would intermittently fail to open. The tail gate and the tail gate window were jammed shut and would not release from the interior or exterior latches. The vehicle was not taken to the dealer for diagnostic testing. The keyless remote also failed to open the tail gate. The contact was concerned since there was no manual release on the tailgate in the event of a crash or any incident where passengers would have to exit the vehicle from the rear. The failure mileage was approximately 170,000. The current mileage was 175,000.