There is zero chance that any Pac 12 expansion would end up being 4 G5 programs that add little to no financial upside. I could see Boise and a tiny sliver of hope for UNLV, given its location, but no shot for NM or SDSU.
They would not add 4 G5 programs but one or two is a good possibility. SDSU is out because they have very little support in their own market and the PAC12 already has strong support in that TV market. No other conference is coming in there to threaten it so they are out. I would give UNM an equal shot with UNLV. Again Vegas is already PAC territory and UNLV doesn't add to that. If New Mexico could get their act together athletically they could dominate that market and expand the geographical range of the conference.
As hard as Boise has tried I don't think they make it. They are a bad fit academically and don't bring a lot in terms of TV market (although their market is growing fast.) The school itself has been subsidizing the program in a huge way and current financial issues may cause that to stop or slow down. They may be past their peak and coming back down, kind of like Fresno did a few years ago.
An argument has always been that certain schools are tied together and come as a package deal. If the B12 collapses that may very well end when schools are scrambling for new conference affiliations. In that event it may be possible to pick up Oklahoma and Kansas without Okie Lite and KjSU coming along
Agree with what Sacky has said before though. The PAC does not have to expand just because other conferences are doing so. Unless it truly benefits the conference and each of it's members then don't do it. Adding Texas may bring in more money but do they truly benefit the conference, that hasn't happened in their past and current affiliations.