They likely still lose, but at worst it's 10-6 at half and more likely given the down and distance with the way they are moving the ball it would have been 10-9 at half. I do think you are correct that if the TD at half doesn't happen, then the game going into the 4th quarter is something like 17-9.
Either way, having Smith is the biggest cheat code for a team I have seen in a long time. Iowa got Ohio State in multiple 3rd and long situations that 95% of the time are stops against any other team in the country and Ohio State picked them up like they were nothing.