My thinking is that the HC'ing job is Fewell's til the end of the season. They all know full well, that he isn't going to be the coach come next season. They bring Shanahan in (or whomever), as the "football guy" that they need in the front office for the remainder of this season, and introduce that person (specially in Shanny's case) as the Head Coach, in the off season
Otherwise, forget about looking for a HC now, unless he's also going to be the HoFO, too.