Zeller is not "so overrated" he does what Indiana asks him to do. He can hit a shot outside of 5 ft, but why put him there if he can get what he does based off dribble penetration.
Iowa played the defense you should against him for the most part, don't freaking help off of him and let him roam in space. Woodbury was also very physical with him and if people doubt he can play physical can let that go. Now it is play physical, but without fouling.
Cody Zeller is a great player and plays within the offense and puts up the numbers he does within the offense. He is one of the most active big men in college basketball, plus he rebounds very well and plays better than average defense.
All that said, I would have liked to see Iowa give Woodbury the ball against him more, like early in the 2nd half, all kinds of spacing against Zeller and he made the shot.