you heard right, I'm setting it up again right now

thanks to the latest patch, the server is now available exclusively to group members. I am unsure if joining through a friend is affected, but if it is, simply invite them to the group! have fun!

So the latest demo patch was just released a few minutes ago, same for the dedicated server files. Here is the changelog-

"Fixed problem with users not being able to connect to dedicated servers

Fix a bug with the group browser not always showing the list of group servers

Fixed a bug with the rcon command"