Hello,
Unfortunately incoming connexiont to Mysql's port aren't allowed on our The World for security purposes.
It would be feasible on a dedicated solution though:
https://www.planethoster.com/en/HybridCloud-Servers
Since our World platform is shared hosting we must apply the best security measures and at the moment the MySQL protocol doesn't support SSL hence why we won't allow this kind of traffic.
On our Premium payable The World platform an SSH tunnel is possible for such applications because SSH is secured. That said your app doesn't seem to support that so there may be need to backup manually,
This is done through the phpMyAdmin interface >> Export DB