Another discourse offline "bootstrap failed with exit code 5"

Not if you followed Configure an S3 compatible object storage provider for uploads. If you have the settings in the database it might be more complicated if you try to do a restore rather than rsync.

Moving to a new droplet is low risk since you can just change dns back to your disabled site, but if you don’t have access to dns and digital ocean you’re stuck.

Sounds like maybe you missed quoting something with the start command. Sounds like that might be what you want to do.

Good luck