Maybe this is some masterful negotiating technique, but Zelensky is out of his mind if he truly thinks the U.S. will deploy peacekeepers to Ukraine. IMO, many (most?) Americans who hear this boots-on-the-ground request will not welcome it at all.
Two years ago, American support for Zelensky was explicitly predicated on not sending U.S. troops. Sure, that was about immediate combat, but I doubt your average American thinks sending U.S. peacekeepers to a recent warzone on Russia’s doorstep is much safer or worth the risk.