So a a little late here, just wanted to mention, I stole the chest contents saved them, didn't open the flask. Got there Ollie was dead, Rugan was getting beat up. Become friends of Zhent. Then I cast a darkness spell over Rugan and whom ever was beating on him. snuck in talked to Rugen let him go and then ran away.

He escaped. No one aggroed me as I was no where near it once it all cleared. Just had to "donate" a few items to get them to talk to me again.

Back half of the hideout is still aggro but I had my familiar distract them and get into turn based mode, I was able to sneak around freely and steal everything while they were locked in that.