I explained above already Juul.
The opponent can still deny Abu.
I don't see a big problem at all, because even if other players are duplicating this action too (saying they got a Fairplay-error as well), the opponent just says 'no' and bam.. he doesn't play.
It can happen to the best of us that something like this happends, no matter if it's Dio, Blue or whoever.
by this,
i dont see any problems allowing dio to play in cups aswell, aslong as the opponent agrees on it. why do we bann people? why do we got rules? you don't see the big picture. you dont see the consequences of your actions. this is a litle example of what will happen in the future, people will abuse this matter.
stop explaining and see what you are doing wrong