You are mistaken. Only if ESPN pulls some strings is anything going to happen- and I highly doubt BYU is a priority in this environment. The MWC could care less about BYU right now.
It sucks, but why would any team or conference go out of their way to schedule BYU right now? They are going to go with the simplest solution right now and scheduling BYU right now is not more simple than keeping an opponent that is already scheduled.
Most likely BYU goes from the greatest schedule in history to the worst schedule in history. BYU is on their own. It sucks, but that's what happens when you are a religious private university in the footprint of the Pac 12 in a world of descending standards.
Life isn't fair.