My MBP won’t start up and I can’t recover it using Time Machine
Is the Time Machine backup on an external drive, a Time Capsule or NAS? Is it possible to inspect the state of the Time Machine backup at Finder level connected to another Mac? You should be able to see the date of the last successful backup and possibly an 'in progress' file which would signify the last backup failed to complete. Try delete this file, it might be the cause. Assuming the TC backups are accessible through the Finder, I would choose the 'Reinstall MacOS' option and install via Apple's servers, then do a restore via the Migration Assistant.