I like to think I have a decent grasp on game mechanics these days, but I was surprised by this one. I thought that the fact that Highmarch was at war with Vix Tiramora would mean they would be going into battle for themselves, not just supporting Redhaven.
It would have made sense to me if Highmarch and Vix were neutral, but since they are at war it seems like they should be a definitive enemy...
Regardless, I think all involved are tracking that now