Gang, I have a messy save where Isobel (Selunite priest) attacked me on neutral response and I had no available saves from before the battle so I had to get verry creative. As it turns out, it's bugged so even if you kill Marcus and every single ghoul, then knock her out - it still cuts to a cutscene with a ghoul taking her away and killing all of the Tieflings (this is my main issue as I'm trying to save).
My solution was to flee to camp and push forward, trying to find another way, as she stays aggro, but only when approached on top floor in her room so the rest of the Last Light Inn was still totally accessible.
Issue is, I made it like another 30-50 hours or something crazy with no new solution and I've found that Nightsong and/or merely entering Shadowfell seems to trigger a conclusion to the quest as if I had ended it poorly, and then everyone dies anyway!
So... I think my last shot might be killing Ketheric without Nightsong and seeing if I can brute force past this issue, that way. The question is: can this still be done in current version? I had read it might not be possible anymore and that perhaps the game truly intends you to solve for Ketheric with Nightsong ONLY?
I don't mind spoilers directly related to the question, just don't stray off topic too far lol