Dont make the NPC who are always part of the event act suprised if something happen over and over again.
Lets take the volcanic vents. latest after the fifth vent druid Olivya should know that she cant "hold it" on her own. Yet she still tries it and fails every tme.
I know its an attempt to make the situation more dramatic, but after a few vents it become ridiculous for the players.
instead of the current sentence, she could say something like "I try to close the final vent but be prepared for whatever come out of it to stop me". There are different end bosses, so the sentece would fit and she would not be suprised by the meanwhile obvious.