I (Abaluk on Thurgadin) had this happen today multiple times when running "Hold of Rime" and "Conservatory" using the free quest chrono baubles from the heralds. Both from nameds and trash mobs. Some are working fine, and then out of the blue I get oneshotted to death. I can't remember ever being oneshotted when using the regular Chrono Dungeons bauble. "Bilkozan the Hungry's Thuri's Doleful Thrust hits YOU for 510.0B crushing damage."
So, 2 months later, it's still in progress. Oh wait, you all forgot about it or put it on the back burner because this doesn't generate revenue?