I chose to poison Simoc. However I failed to convince him to take the poison and fought him. I won but then were stuck. My party was in combat mode since Lliras was still alive. I could not complete the quest as I could not talk to Lliras in combat, could not attack him, could not leave the Hall of Warriors in combat, could not save, etc.
I had to quit and reload from a previous save, and abandon the quest.
Thanks
James