Restore Purchases says the restore is complete but it doesn't restore any or all of your purchases.
You may have bought the in app purchase(s) in question in the free version (TowerMadness Zero). Try downloading TowerMadness Zero from the App Store and trying to Restore Purchases from within TowerMadness Zero.
TowerMadness Zero purchases transfer to the iPad and full version of TowerMadness. In order to do this, you must restore any purchases made in TowerMadness Zero to get them back in the full version of TowerMadness. You may need to restart your device after following the steps above before you see the restored purchases reflected in the game.
If you are on a different device than the one originally used to make the purchase, you must install the application using the same iTunes account used to make the original purchase.
If your device was used with more than one iTunes account, make sure you're logged into iTunes using the same account used to make the purchase(s) before attempting to run Restore Purchases.
Finally, you may also need to restart your device after following the steps above before you see the restored purchases reflected in the game.