That's not how it works on a decent VPN system.

If you try to do that, the VPN client will notice that the spoofed server isn't presenting a valid certificate or doesn't use a valid key, and refuse to connect. Same reason you can't "just" middleman an HTTPS connection.

Besides, there's no need to spoof. The point of the VPN connection is to protect against the wifi router (even the legitimate one!) reading the traffic. By spoofing, you're just replacing a dodgy wifi router with another dodgy router.