So the Artifact weapon questline for Assassination is impossible to complete

Yeah, on my Warlock that part where you have to use Demonic Gate, it showed up as an extra button even though my char was only level 12.

OTOH, for Monk when I was doing the healer staff the final battle where you’re supposed to get a group of NPCs that you need to heal, it didn’t work.
The NPCs kept popping in and out of the group, and scattering all over the map so I couldn’t find them.
It took 4 or 5 tries before I could get them all in the same group and the same place at the same time and actually finish the battle.