[sYc]

It looks like he was towing with a one ton, four door dually. If that is the case, that car, on an open trailer, could be loaded on the tongue, on the back, anyhwere, and not be a problem. And even if the trailer brakes were not working, would still stop in a reasonable distance.

As per the ball, my guess it snapped when the trailer jacknifed, hitting the truck. Just think of the force that would create (leverage) when that occurred.