Hi,
I am a very satisfied user of Plex for a long time. I have a dedicated server outside of my network where I have the server installed and I mainly watch videos on my Windows PC from either the web version or the app. However I would like to be able to use the remote control options from my Android device where I have the latest Plex app installed. Under the settings I have these set:

Yet the Windows based player doesn’t show up in the Android app and therefore I cannot control it. Any ideas?
Edit: Just to clarify, I have the firewall disabled.
Thanks