This is what happens when you have too much tongue weight...

Probably a combo of all of the above, IMO.
No, the torque of the driveshaft wouldn't be enough on its own. Something in the driveline would snap, assuming it was stock.
No, the tongue weight wouldn't do it alone and neither would the camper overhang.
Tie downs welded to the frame if that wuz the case before the accident(s)? Would also contribute.
As well as road conditions (bumps).
Usually not one to revel in others failures, but there's still some wow factor to these fails!