They did not die because So Mun manage to get back his power and manage to save all of them from the fire.  So Mun ask Wi Gen (his partner) to go back in to his body so that he could protect and save them..  Hope this will clear your query🥰 Also sorry for my broken eng😅

I think it's becaise of their ability. I think the explosion isn't enough to kill them..  If they were just normal people they would probably died from explosion. But the explosion isn't enough to kill them. And So Mun also summon the territory shift. When he did that their abilities increase 5x and that's probably one of the reason they manage to survive the explosion. I'm sorry if my question last time didn't answer your query😅 I hope this time it will.

(P.S. thank you❤)