Apple Configurator 2 padlock and not MDM

I've got a customer's MacBook Air (Retina, 13-inch, 2018) that I've tried to revive using Configurator 2.

as per https://support.apple.com/en-ca/guide/apple-configurator-2/welcome/mac

Following Revive or restore an Intel-based Mac with Apple Configurator

This does work: Actions > Advanced > Revive Device and click Revive.

Sort of, it goes through the process but comes up with a Padlock Symbol. I can't find an answer for why that is appearing. Find my Device is off so my suspicion is either a hardware failure or something with FileVault or encryption.

I'm sharing this just to see if anyone else has encountered this.