I need some help. My friend and I want to play a game on virtual LAN. We use Radmin VPN. We can both connect to the Radmin network no problem. However, his game does not detect the Radmin IP. It detects his LAN only. We tried setting the metric to 1 for the network adapter, no success. We tried Force Bind, still doesn't work. Tried using some vpn other than Radmin, same issue.
no matter what, his game doesn't bind to the VPN IP. What can we do?

There are two interfaces. Radmin and his Ethernet. The game detects his ethernet adapter
but not his radmin adapter. Because of the viral outbreak the ISP cannot help
him, lack of manpower. I tried, but i couldn't fix it. And I can't ask him to troubleshoot like that cause if he messes up by shooting in the dark, the ISP won't be able to help him.
Can you provide me some details on your AOE2 setup? here are some questions I have
1) What version/patch of the game are you using?
2) Do you use the Wololokingdoms mod? If yes, have you used Aoe2Tools to setup WK mod or the WK Installer?
1) Remove port forwarding for aoe2 on your router if you had set it up
2) Firewall exceptions for age2_x1 or age2_x1.5 (I suspect this could be the actual reason)
3) Remove all other VLAN services u installed and keep only Radmin
Cold boot both router and PC
Other VLAN services were disabled.
He doesn't have public ip, so he didn't port forward.
It seems that this game is not able to work with Radmin VPN because of different IP ranges.