The right roll is not "caused" by a low G scenario, but because the pilot has not reacted to it. As the rotor disc unloads due to the down-draught and pedal settings are not changed, the nose will yaw left which will begin a right roll through parasite drag on the fuselage. The manual recommends the aft cyclic input before lateral etc.
Now take a step back to the down-draught and as the low-G feelings come on, watch that very expensive piece of string attached to the bubble. If you keep it in balance by adding some right pedal, I'd bet my beer fridge and it's contents that the roll won't happen.