Of course CSU is being vetted. Any legitimate school that approaches the Big12 will be vetted to some degree. CSU may not make the top 2 or the top 4, but clearly they deserve at least courteous attention from the Big12.
While the Florida schools seem to be last on many lists, I suspect that it is very tempting for some schools to add one FL schools for recruiting, warm weather destination, and additional media market exposure. There are clear weaknesses with both schools, I'm certainly not betting on them. I just think it's an interesting factor that will be hard to overlook, particularly if the conference goes to 14.