Thanks for your reply!
Yes, that makes sense.

We need a way to silently connect a player to another server (without any player made interactions)
The idea is to have a main server, via sqf the mission is able to forward a player to another server, but atm thats not possible, when the player is connected to a server (in editor, it's working when I call a function in a dll, which creates a process with the steam:// way to get that working)

Another problem is, we dont know how to completely disable the player slot assignment / role selection (this would be really nice to be able to).
Of course, a slot has to be auto assigned as currently with "joinUnassigned".