His inability to check down is a separate issue. To me, it seems like the coaches are explicitly telling him not to run unless all his options are covered (and he can't see who's open and who's not, which is, again, a separate issue)
I firmly believe that Caleb refusing to tuck and run is something that is being coached out of him. We know (from last year) that his instinct is to run before checking down, and now he's going out of his way to keep the play alive without running. That HAS to be coming down from the coaches