MostSaneWatcher

Thanks, I just tried again, and got it to work this time. If you make any noise while invisible and alert them at all (even if you don't actually start a fight), then it won't work and you need to retry. Was a bit tricky since there's a thug standing literally right in front of the apothecary, but crouch-walking around him worked.

I just tried this, but no luck for me -- when invisible and the resurrected Thalla is still alive, there's still no option to talk with the apothecary. I did try it on some other NPCs though and you *can* talk to them while invisible, which is kind of funny.

Just happened to me as well. Killed Thalla (normally) hours ago, now I need to talk to the apothecary for the main quest and I can't. When I approached the apothecary, Thalla spawned in, I killed him again, and he immediately despawned without the death animation. Reloaded, fought him again, killed him again, and he died normally and dropped loot this time, but I still cannot talk to the apothecary. Saved and then loaded the new save, and Thalla is gone, but I still cannot to talk to the apothecary. This seems like an issue you can stumble into pretty easily, hopefully a patch isn't too far off.