Dark Event Added before Mission to prevent Dark Event begins?!?

[caseywills]

This is very irritating.
I was about to run a mission to prevent a dark event, but the event has already been added to the active list?!?
I think the dark event is added when the mission timer hits zero, and doesn't wait for you to actually run the mission. For these missions you cannot wait for the timer to hit zero. You do not get any buffer as with other missions.

So I run the mission anyway, and win. And am feeling cheated.
I've been looking for a way to use the console commands to remove the dark event from the active list, but to no avail.
Its a particularly nasty one (Tac Defense).
ugh.