I think at this point the best solution would be for Nika to not be William's son. I would have prefered Nika to be a part of the Zane dynasty but i guess he can still become that through marriage when all LI's are kinda Zane's
Maybe .. i dunno .. William has a cool buddy during the story of wiab who kinda sacrifices himself for willy or a zane girl and thats why the Zane's keep having an interest in Nika and Willy could even still be the "uncle" (not blood related) who teached him basket ball as a close friend of his father.
But no clue why Nami would be with them in this case (if shes willy offspring), even in case Daphne died.
And anyway, i have to agree with
Dr.TSoni the whole existence of the Nika/Nami situation in SG should speak against no incest at all in SG ... in theory ... who knows ..
On the bright side, it cant really get more confusing