I recently got confused with Angelic Buster's questline when i left the heretic temple after accepting magnus's plan (매그너스의 계획). when I cam back, the cutscene with the 3 priests seemed to not be triggering. I searched the web for solutions but all I found were some unanswered posts.
even though this is just a link mule it was bothering me so I decided to try and figure it out
after trying the usual things like forfeiting and re-accepting the quest, I noticed a post on inven that directed people to a different entrance for the heretic temple. and then it hit me - there are two heretic temple maps, one with red monks and the other one with blue monks and i was going to the wrong one. they look almost the same so I didn't notice