If you read through the comments on the video, the alleged owners admitted that they were on the way back out of their predicament. They had finally found a place to turn around to go back out after having sheared off their front A/C unit and side awning on one of the two tunnels they had already passed through. Others mentioned that there are numerous "No RV/Trailer/Truck" signs prior to the tunnels. The owners admit that it was a very new (first outing?) trailer.