Legal double/triple trailers, in every state, don't use ball hitches. The coupler is a pintle (and NOT the ball-pintle adapter). Different animal, altogether. A ball-behind-ball combination isn't legal anywhere that I'm aware of. They are not legal for a reason. For the same reason, you can't double/triple behind a gooseneck. The forward towed vehicles must be 5th wheel, or pintle (triples).

Pursue it if you wish, but it's my guess the only satisfaction in the end will be had by the lawyers.