The B12 just doesn't look particularly solidified. Intensity looks lost, but that may be a temporary impression. If the PAC12 wants a few more from there, maybe that opportunity shall happen. PAC12 Commish Scott seems reluctant to push for another expansion move anytime soon, given the earlier frustrations after he was first hired.
I think the PAC's problem these days is having indecisive programs with an ambitious commissioner. The PAC would have made VERY respectable money by adding OU and OSU, but they balked. Then, B1G-PAC fell apart thanks to USC and a few others, despite it being agreed on initially.
So, it sounds like the schools have made the conscious choice to not make more money. I just hope they'll remember that when other conferences start making bank with their pulls. Chances are, they'll conveniently forget.
I don't know what happens first for them: Larry Scott loses interest in the PAC, or the other way around.