Had the time to test this now. I wrote a small testplugin to log the output (if any) and nothing happened. So I looked more closely if both the extension and the plugin loaded successfully and they did. So no message is logged, neither on allowed join nor on a blocked attempt.
The console of the blocked client(!) shows this
Code:
CSysSessionClient: lobby response 10!
I am giving you this because I think it might be helpful.
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