Agreed. At this level of football (FCS), you have to accept (and expect) the possibility your coach may leave if you’re successful. Quite obvious when looking at NDSU over the past 10 years. And there’s no way Bubba fits that category at this juncture.
There are several potential candidates for hire, whether coordinators in FCS or even low-tier FBS schools, FBS position coaches, and probably the most popular would be current division II head coaches who have been very successful.