Monster Hunter Portable 3rd (HD Ver. or not)

[Relic1882]

Quick question. My 2 sons and I are enjoying Portable 3rd HD on my computers in the house. I'm running the Ad-Hoc server console on one pc, and all 3 pc's are joining to that server using the local ip 192.168.1.7. Everything is fine.

Now, I gave my internet ip, (72.etc.etc...) to a friend up the road that wants to play with us, but we cannot see him join in the room and he can't see us. Port 27312 is opened up on my port for the host PC too. I DO see him joining on the Ad-Hoc server, but we can't play together. We're all joining the same guild hall manually. Firewalls have permission to allow AdhocServer.exe in full, and I even went as far as to try disabling my firewall altogether. Fast Memory is UNCHECKED on all pcs and we're all using different random Mac addresses and different console nicknames. What am I missing for him to join us? I just can't get him to see us in the room.