Kyuubi might have influenced Naruto's emotions at this point but it was still Naruto's decision. That he was able to make that choice at all, no matter that it was under extreme emotional duress, is good enough for Sasuke. Besides now he's a bit less crazy with the need to leave everything behind, so he doesn't need a threat level quite as high. They do need to talk about that time, though. Naruto's been doing his best to pretend it hasn't happened since Sasuke refused to listen to him back in the day when he tried to apologize.