In my case, after the dealer replaced the pinch strip, I didn’t have anymore issues with the liftgate.I know it’s an old post but I figured it was worth a try. Did changing the pinch strip solve the issue ? I have the same code but I can’t get the liftgate to release or openUpdate:
Dealer replaced the pinch strip on Friday and while it's still there waiting for my Turbo I checked and it's working now.
Assuming that your issue is the actual pinch strip, and not something else, replacing the pinch strip should fix it.