My
I don't think the trailer is a fiver. We are looking "straight down" on the roof in the picture, so it makes it hard to tell, but I do not see the tell-tale humped roof line that all fivers have.
If this were a fiver, they would almost surely still be attached. Every fiver rollover I have ever seen (just pics, thankfully never one in person) and every semi-trailer wreck I have seen, the TV never comes loose of the trailer.
Now if a standard travel trailer jack knifes, hard enough, I could see the trailer wanting to roll over "into" the truck bed as it comes uncoupled, assuming everything is moving in the proper direction.
That's my theory, anyway.
My backup plan is the trailer fell on the passing truck just out of bad luck, and the truck is not the TV for the trailer at all.