Watcn useless due to "watch os unable to verify update"

Updated iPhoneXR to iOS 14 trying to update my Apple Watch (series 4) too. Watch app said I needed to pair with my Apple Watch again. I paired them and was told it needed to be updated. Download the update and but get the dreaded "watch os unable to verify update" despite my being on WiFi and next to phone.

Nothing works.

Have gone through steps on unpairing my watch/phone to get out of update screen. Restarting everything, factory resetting Watch, changing WiFi networks. Aple Watch app on phone and all the work around in all the help articles I see are useless as I cannot get into setting on either watch itself or watch app on phone since they're unpaired.

Watch is effectively a pretty paperweight at the moment as it cannot pair to my phone updated or not.

Help!