On 4th and 3, down 3, with Cooper and Zeke healthy, you call a play to showcase your new toy.
You ask a rookie to run a crossing route and he cuts short of the sticks. The Rams could only make a play because either the coaches didn't teach him to run it to the sticks, or CeeDee is a dumbass rookie with a two letter first name. And Schultz does deserves some blame too for not understanding he was doubled and not plowing forward to get deep enough to pick the safety.
And on the formation, put CeeDee outside of the other WR so the other WR can influence both CBs and the safety and then CeeDee crosses behind him, i.e. the classic pick play that the Pats have run for years.
The Cowboys philosophy is still the same as ever. They need players to win matchups because they don't scheme for shit.