Actually this was pretty interesting idea. Never thought about having issue with netword card. I have desktop PC, so I'm connected via Ethernet and can't connect through WiFi. BUT. I have a laptop. So I joined my laptop to our room. Relayed tunnel with my friend again. Between my PC and laptop is direct tunnel, which make sense cuz they're on the same network.
I believe the problem is in my router somewhere, because we had direct tunnel with my friend and everything was fine. Then my router broke and I had to buy a new once. Since then, we have relayed tunnel.