When the DB was "restored," Did the user restore from the filesystem backups?
If you have the SQL files dumps, you should try restoring that data on a separate system where you can install MYSQL if not installed and restore them from the sql dumps,
Hopefully, you have the DB/table create as part of the SQLs and the sql backups are recent enough.
The only time a filesystem mysql backup will be valid is when mysql is not running when the backup is taken/made/created. If you have no opportunity to do recovering files that way, then I can advise to try to take MySql Recovery Toolbox and restore file using this tool and think you will be able to save your base. http://www.oemailrecovery.com/mysql_recovery.html
You can still read this resource for more information on your issue.
https://community.office365.com/en-us/f/172/t/266451