Update on my specific situation… I still had files in my /var/discourse/shared/standalone/uploads even though I had switched over to S3 for storage. Once I deleted the ‘default’ directory in that uploads dir I re-created a backup it successfully created one that was database only (…sql.gz).
For some reason (in my case) if there are files in that directory it ignores the setting to NOT include uploads in the backup and creates them anyway.
Let me know if any more information or clarification is needed for my situation. Seems like it is maybe slightly different than the OP’s situation.
Either way I was able to get around the problem and can successfully restore now.