Using Kodi to Access Serviio Remotely

Here’s my setup:
Windows 10 x64 Server running Serviio Pro. and SMB Shares.

Xiaom Mi Box in living room, running Kodi
Desktop PC in office, running Kodi
Laptop, Android Phones and Tablets all running Kodi
Kodi is up to date w/ Ver 17 on all devices.
Devices are able to access Kodi via SMB shares while inside the network.

I have ports opened on the firewalls and routers to access Serviio externally and use its MediaBrowser component.
I am able to use the ServiGo app on android devices while external to the network.

I would like to be able to use Kodi as a Front End for the mobile devices by accessing the same connection that MediaBrowser and ServiGo do.
I have tried to set this up by adding a DLNA source, but it is my understanding that UPNP/DLNA does not work across networks.

Is there any way to do this with or without a plugin?