The review booth could not have overturned anything even if they wanted to.
Big Ten's coordinator of officials, said in a statement after the game, "They can't review whether it was a force out/contact on the play. They can only review if there was clear evidence of no contact and he (Reilly) re-established himself in the field of play. If he goes out of bounds on his own with no contact, it's an illegal touch. Therefore the call stood."
The defender is looking back to the QB the whole time, he has a right to position himself on the field just as much as the offensive guy. There is no forcible contact here, he ran out in his own accord.