trugg..Welcome to iRV2 !
I think I remember seeing a number stamped on a plate right by the front door on our old Bounder- but I could be wrong.
Did you buy it from a Dealer? I would call them if you did. (They should know where to locate the other sticker. ) If that does not work - then I would contact a local RV dealer who carries the Fleetwood brand. The dealer should be able to tell you (or they can contact Fleetwood directly on your behalf) where you can find the other VIN plate.
Good Luck...I hope you are able to get out camping soon!!