WR can use his bands to slow local time to a near-standstill, or stop it completely. However, Zoom exists in a 'time bubble' which is completely separate from the main timestream. Therefore, you would have to single out the specific 'time bubble' Zoom exists in, to slow him down - and personally, I doubt that is something WR would know, or even attempt the first time around.
So if this were a single battle, Zoom would take it rather easily via speedblitz. If this were a 'best out of ten' type of battle, WR would probably figure out how to stop Zoom, and take the majority. Imo.