Originally Posted by alex67500

You're overcomplicating things, and trying to do things you can't do. You should book the 4 seats with your 2-4-1s when they become available and set an alert for one seat on a site like seatspy or reward flight finder for the 5th. If none show up about 6 weeks out, then use a gold priority reward. You'll have to be on the first booking as the owner of the vouchers.