Edit: Okay, so while this particular pre-event seems bugged indead (where you need to revive Pact Soldiers), it does not seem to halt the overall event chain.
Sorry, I just don’t (and probably never will) get the logic behind the timers of all the Orr events. The events seem quite messy, way to entwined and randomly timed. I’m glad the devs did not continue on this path with later maps.