Connect android emulator to lan
I think  that if you add the IP of the server on you LAN network that will  allow you to access it from the emulator.
So a fight with iptables is required in your case 

useful links https://developer.android.com/studio/run/emulator-networking.html

and there is a hole bunch of documentation of how to redirect network traffic to a new IP address using iptables

Good luck i hope my answer was useful!