Sure he can transfer after he graduates, but that doesn't mean that other schools can contact him. In fact, it's an NCAA violation for any other coaches or boosters from other schools to try to influence him to transfer. If they actually do put up billboards, anyone who donated to the "cause" who has ever bought Utah season tickets in any sport (and is therefore considered a "booster") will have engaged in an NCAA violation. In fact, if the dude (or bleached mustached female) who put up the gofundme page is considered a "booster," Utah has already committed an NCAA violation.