It wasn't press coverage... so Arian was supposed to break off that route, regardless of whether or not the defense was playing zone. Ended up with the Cowboys being lucky as there was nobody deep.... but its still a route that needs to be read right at the LOS.
After that replay, I think foster picked the deep option and Fitz didn't see it. No help over top, would've been an easy TD if Fitz picked up on what arian did that was on ritzy
With a better QB, Texans would be up 7-0 right now on that pass to Arian. Fitz with bad read on the route.
The problem is, the pre-set route is determined at the LOS... Foster only sees this after the ball is basically coming out. Sure, if Fitz just improvises and holds on to the ball, they may have a TD on busted coverage... but that wouldn't be because of the play-call at the LOS... would have been more "street-ball".
Right... press coverage would have led to Foster going deep. Thus, since it wasn't press coverage, Fitz read it as a stop/comeback/out route that Foster "should" have ran.