I'm happy nothing bad happened to you.
You didn't say if its a 3-piece ball or not.
I don't know about NY, but they've been illegal in Canada for 30-some years. The were notorious for the nut coming loose, even with lock washers and stuff like loctite, and causing dangerous situations. Don't know why they did that.
100 - 120 ft lbs or so should be more than enough to secure a ball on the hitch with a lock washer.
I'm sorry I can't answer your question if the ball wasn't a 3-piece.
I never heard of solid ball coming loose with proper tightening, even on "big rigs"
IS it a 3-piece.....? If so, get rid it PDQ!