One last attempt to make this work before removing it forever SOLVED!

I suppose one element making this tricky is that there’s a number of different flavors of Linux systems handling things differently when it comes to this.

Have you had a look at the related support article?
https://support.plex.tv/articles/202529153-why-is-my-plex-media-server-directory-so-large/ (section " Relocate your Plex Media Server Data Directory")

In this section you’ll also find a link to one of chuckpa’s forum posts where he breaks this down for the different Linux distro types: