Not a basketball rule expert, but what I got from what the announcers were saying: the player with the ball has a cylinder of space to move within. The defender encroached in that cylinder and got hit. It’s not the offensive player’s fault that the defender encroached in that area. So no foul.
That being said, the defender was pushed by the illegal screen which wasn’t called. If the illegal screen had been called, it would have been a foul too.