Should I go to Nightsong or kill everyone on Moonrise first?

I 've read some posts, but I didn't really get a good picture.

I am at a point where I 've talked with Balthazar, completed the Shar gauntlet, and I had also freed the tieflings and Minthara in Moonrise beforehand.
Will I have the chance to kill everyone under Ketheric's floor once I 'm done with him and loot them?

Thank you!