Couple things people seem to be missing... It wasn't confirmed that Sasuke doesn't care, it was just confirmed that he is putting the rest of humanity above just 2 people, few for the sake of many type thing.
Another thing is sasuke was remembering his time on the bridge with naruto and understands him but is trying to remain level headed in the battle because he feels that his responsibility is to keep naruto alive (and vice versa, they are actually friends)
We don't know whether or not Kaguya's castle was in another dimmension or was actually on earth itself, so that is still up in the air.
I don't see how the Edo Kages will actually be able to help, not questioning there power (the fact that they can't sense the chakra is a good indicator that they traveled into another dimension) just I don't know what they could possible do to help.
You can't explain anything about Sasuke to these Naruto Balls Boys, cause they are the biggest Sasuke hater ever.
You would think after the Neji death episode in Shippuden, these Naruto Bottom B's would think their pimp Naruto would put the whole world, before Sakura and Kakashi (this dumb a$$ would risk the whole world to save Obito).
So all these Hinata's accused Sasuke of being in the dark cause he is making the hard decision for the greater good, like a true leader/boss need to do (I made a quote in chapter 677 that Sasuke only save them cause they were next to Naruto and he know he need Naruto to save the world and all Sakura and Kakashi can do is get in the way).
Guess what people Sasuke is not a good boy puss like Naruto. Sasuke is a crusader for the greater good of what the best for the world and forget friendship, love, hate and his clan (that why he wanted to kill the Juubi and all the tail beast, cause this can never happen again).
