They were not designed runs for Dak Prescott.
Dallas almost never calls a designed QB run.
The read option allows for either the RB or QB to run the ball depending on how the defense reacts.
When the unblocked edge defender crashes down on the perceived inside hand off to Ezekiel Elliott, Dak is supposed to pull the ball back and run into that vacated area.
If that player stays in his lane to respect the threat of Dak keeping the ball, Zeke gets the inside hand off and has one less defender to worry about.