did you disable DHT in the client?
That video is older and unraid has made jumps in networking. with that being said its good that you tried it. Going to muddy the water but recently this user release a new container with similar name to this one. In the new container he was incorporated gluetun so that changes the how it connects to the vpn service. I used the older container but I do not use the vpn or proxy part of it because in case the vpn fail I don't believe the container had a way to stop leaks. I believe once you add another container to use this as it outbound networking you have to map prowlars ports to be exposed so you can get to the webui. I dont know what version of unraid you are on but this video from spaceinvader explains the new networking implementation.
Unraid Container network
Sorry to derail your post.
@PANDABOY
Hello!
Thank you very much! After your guide has been tested, we are going to split your message in the "How To" forum and make it a guide for Plex remote access via Proxmox on AirVPN.
Kind regards