If LeVar has only worked at Iowa, where are his connections to hire an innovative OC? Every coach he knows has come through Iowa. Sure he could cold call OC's, but typically that's not how coaching hires work, head coaches want guys, that they have already relationship.
As far as running spread, one of the problems Iowa faces is that their lineman are not the most mobile/athletic, when the offense spreads out the field, that exposes lineman to having to cover more space and speed. If the game is played in tighter spaces, that lack of athleticism is hidden. Making that personnel change could take some time.