The painter in the Zhentarim Grotto asks to be freed by paying the Zhents.
I however decided I wanted their treasury and cleared out the hideout.
However once I cleared it the painter still talked about asking his caretaker to buy his freedom despite noone alive remained in the hideout, softlocking the quest.
While not the most elegant solution to his predicament it should definitly work or atleast prompt him to freak out regarding the rest of the Zhents future retaliation.
Make sure you kill the guy in above the hideout too
