Example of what I am trying to do:
VPN / Split Tunneling off: Anyone can connect to my server using 1.2.3.4:1234 port, however, when I enable split tunneling for a specific app for example browsing the web. I do not want the VPN to affect the server. However, once Split Tunneling has been turned on, no one is now able to connect to that server. I suspect it has something to do with the NordLynx tunnel that gets created, but I am unsure of how to route it. I can see that the app that I want to get split tunneled works as expected, however, my dedicated server should be able to work and it does not.
On my router I have my ports forwarded, do I need to perhaps forward them to the IP of the NordLynx tunnel?
Right don’t quote me, but I’ve got a hunch the issue here could be tied to the way your server’s IP addresses are being handled…
So basically when the VPN is active, your public IP is the one assigned by the VPN. Since the
server isn’t connected to the VPN (due to split tunneling), keep port forwarding to the server’s local IP on the router.
Let me know if that makes any sense haha, and if so, how you get on 
Since the
server isn’t connected to the VPN (due to split tunneling), keep port forwarding to the server’s local IP on the router.
What do you mean by this? He is already port fowarding to the local IP of the device that has the server. That is why the server works when he turns off NordVPN.