Safety chains are certainly not a bad idea. I’ve got a standard FW hitch and nearly lost my trailer at highway speed. We’re it not for my tailgate folding into a V with the kingpin imbedded in it, it would’ve been a yard sale. I drug it for a few moments like that on the landing gear till I figured out what was going on and was able to slow and pull over. Never good to look in the mirror and see your trailer is there, but it’s further back and lower than it should be.
It was user error(me), but if it can happen with a standard fifth wheel hitch I’m sure it can happen with a ball attachment.