Did he have any injuries on his left hand or arm?
I ask, because about 20 years ago, I was in a league with someone who had to wear a glove and pressure garments underneath what would now be a compression sleeve due to having suffered either 2nd or 3rd degree burns on his arm and part of his body, and his body hadn't totally healed up from it. So as long as it didn't impact the release off his right hand, it was fair game, plus while he did play fair, no-one would have called the rulebook into play on him without coming out sounding like an ass. Everyone in the city knew what he had been through and knew it was legit.
BL.