Guess we'll find out how savage Nikaku is now that his big bro's been beaten up bad, and whether he's the one who kills Meguro or not, and if Meguro is actually dead. That image how him with his brain spilling out could just be a dramatization of what was reported, which might have been a lie to draw Tanzawa out. As for Yoshiki, he can say he isn't Jousuke all he wants, but I think he'd go just as far as Jousuke if someone asked him to. He seems unable to say "no" to people he cares for.