I found a similar solution and it worked perfectly. These are the exact steps I took:
1. Boot to recovery
2. Launch Terminal
3. Run terminal command: resetpassword
4. Click on the Reset Password window , then choose Recovery Assistant in the menu bar then select Erase Mac.
5. Click Erase Mac in the window that opens, then click Erase Mac again to confirm. When done, your Mac restarts automatically.
6. If you are on 11.0.1 it will automatically reboot after the erase is complete. After the reboot select wifi appears, and will prompt you for activation. When activation completes, you need to choose the option of [Exit to Recovery Utilities] which brings us back to the main recovery screen.
7. If the activation fails, make sure you are connected to the internet via your Wifi icon.
8. Once activation is completed. You will see the normal restore options. Choose reinstall macOS Big Sur.
Credit: Blackhawkdriver (macrumors)