How to Connect to your Server
Open your server Control Panel & navigate to the Network tab.
Copy & paste your non-primary Hostname & Port into your Steam server list.
In the Steam toolbar, select View, then Servers.
Under the Favorites tab, select Add a Server.
Paste the Hostname & Port. It should look like:
xx.xxx.xx.xxx:xxxx
or example.protoncortex.com:xxxx
Select Add this Address to Favorites.
At this point you can find your server under the Favorites tab in-game!