They clearly are related or close friends with someone who is associated with an NFL team front office. Whoever gave them the number doesn't like Sheduer personally.
Unfortunately, it's not a crime to prank call, as long as it doesn't include threats and harmful messages. He should've known it wasn't real when they kept mumbling and saying “uhh” in between words; a professional front office executive, I imagine, would have better communication skills.
I know he had to have been devastated and low-key hurt when it happened; I would've called them back and told 'em to go fuk themselves, whatcha got to lose at this

? It's fair game.