Plex is a taboo topic anymore because of their recent business-focused changes. I personally use Plex as I’ve been a user since the early 2000s with no intentions to learn the nuances of Jellyfin, and get my remote streamers moved over to it.
Plex mixed with Sonarr, Radarr and Overseer fits my needs perfectly.
Wireguard IS a VPN. He has somehow through his challenges of exposing services to the internet, exposed wireguard from his home to the internet for him to connect to. Then he can connect to his internal services from there.
It’s honestly the best option and how I operate as well. I only have a handful of items exposed and even those flow through a DMZ proxy before hitting their destination servers.