I'm reading a post about your truck camper falling off the truck, and the replys are about a furnace, gas lighting, and other non-related topics.
Also, kind of sucks photobucket puts a their watermark over a significant amount of each image. I see lots of screws going through a piece of aluminum box that either pulled out of something or nothing. My old 2000 S&S has had some pretty hard slams and all tiedown points are fine. Rather than the tiedown points pulling out, the hook ends on my turnbuckles bent straight. I see no reason to use fastguns or similar over simple turnbuckles. The spring in the fastguns may even allow for acceleration of the TC mass increasing the breakaway force. A solid turnbuckle will not allow that freedom of movement. I'm sure there will be plenty of expert argument over that suggestion.
The main thing is, you and your family are fine. Any landing you can walk away from as they say. Best wishes on getting a replacement and back on the trail.