Why would a failure of a backup system require editing everything again? Something must have gotten lost in translation here.
Raw rushes are still available on the original disks/cards, but the project files and any renders were stored on a single location with no backup or snapshotting.
You'd have to redo everything from scratch. Maybe your editor/director remembers what they want so its a bit faster this time round, if they are available, but its still a lot of work to rebuild the edit.
Could be a combination of factors:
1. AI agent deletes the primary copy 2. Backup system fails (when did they last test the restoration process?), so they have no copies