Nextcloud AIO on VPS and TURN server for Talk


I have Nextcloud running on my own server at home without any issues.

I have deployed the Nextcloud AIO on a cheap VPS and only enabled TALK for Turn Server.

Now on my own server I have entered what I have found in the AIO VPS settings. (see the screenshot).

Now with these settings in my own server, what can be seen from the VPS side in case some one hacks in?
I’m assuming that there is nothing else besides my IP address and the person who I’m calling, right?

From my understanding, anyone who knows the VPS domain can use my stun server, right? I’m referring to the 3rd stun: at the top, the other two have some sort of secret.