I really don't think Aikido would work well in an NHB scheme. (Not from an effectiveness standpoint, but a money making one) Promoters want 2 gladiators to bludgeon or grapple to submission or unconsciousness. I teach at a crosstraining school and I get a chance now and then to open spar. The NHB fighter will try to quickly close the gap with kicks punches or takedowns. An Aikidoka will keep proper ma-ai, which doesn't play well into a NHB fighters game. Plus, irimi and tenkan movements are very surprising to an NHB fighter.
What happens alot with me is that the NHB person stands there and gets frustrated not seeing any openings and winds up throwing themselves at me. Game over.
Aikido is patient...NHB is not.