I would love it, but I dont see it happening. If Any PAC12 team cancels their game, they will get Washington.
If any of the below games are cancelled for the week o fDec 5th
Washington State vs USC (could play either team)
Oregon vs Cal (they already have Oregon on their schedule but could play Cal.)
UCLA vs Arizona State (could play either team)
Colorado vs Arizona (already played Arizona, but could play Colorado)
With how the PAC 12 has gone each week during this "season" I doubt Washinton will be available at any time. For that matter, I doubt any PAC 12 will be able to play BYU or even any non-Conf team.