This is a terrible idea, i'm just highlighting this for the next person, please do NOT do this, there is a Web UI for urbackup for a reason, please delete images and backups using the UI, otherwise urbackup will be unaware of your manual deletion.
This is the wrong path, the urbackup databases are located at /config/urbackup/
TBH i would recommend you try asking for help on the urbackup forum, they should be able to guide you on the best way to fix this.