I apologize for the trouble you've been having but downgrading the firmware will not solve the connectivity issues.Especially because you've tried to re-add it and it most likely also changed the node ID and not even a backup will restore it.
Make sure you are excluding the lock from Vera with the lock near the unit(5 feet max with new batteries in the lock). But try to use the exclusion procedure, don't simply delete it from the interface.
If you have the lock on your interface with the error, press on "Delete" and when prompted, select "unpair", and do the unpairing procedure on the lock(check the manual of the lock). This will also delete any residual settings from the lock and if the procedure was successful, it will also disappear from the dashboard. If it's not getting detected during the exclusion procedure and it does not delete it from the dashboard, then either the lock is too far, or you are doing the wrong steps on the lock.
Then try to add it again, after it got deleted, and if it's within 5 feet, it should get detected and not fail at getting the manufacturer or else.
If you are still having trouble don't hesitate to contact tech support over the phone or email at email@example.com
so we can troubleshoot the setup and see how we can identify the issue and resolve it.
USA Toll Free: +18669662272
Hours of Operation: Monday ? Friday 12:00am to 6:00pm Pacific Time