I don't think Jok will start, but if things aren't looking good for the Hawkeyes I think he plays. I think he'll still be a bit limited, though.
We are a better defensive team than Ohio State. We need to make sure to get out on Ellingson, though, who is lethal from range and will be seeing expanded minutes if Jok is on the bench. We have the best 3P% defense in the league right now... but Iowa puts up 21 threes a game on average, accounting for about a third of their overall shots (Ellingson went 5-7 against OSU, and is shooting .537 from behind the arc so far this season in limited minutes).