Jellyfin Kodi Add-On Mode. What's wrong?

Having some issues understanding how this Kodi plugin functions. I am a loooong time Kodi user and manually manage multi-user MySQL databases across multiple servers/households. I am super stoked on finally moving my backend to Jellyfin!

My Setup

  1. Docker on the server.
  2. docker-compose with the image.
  3. Jellyfin is mounting my media volumes locally, NOT over NFS or SMB.
  4. Open the web UI and scrape all my media saving NFO and image files directly to the folders where my media lives. Works like a charm and everything looks good.
  5. Client devices are Amazon 4K Firesticks with Kodi 18.9, as well as Android phones running Kodi.
  6. Installed Kodi’s Jellyfin repo on all devices and setup Jellyfin NOT Jellycon.
    This is where things confuse me…
    After reading the docs, it states you can operate the plugin in two ways:

Add-On Mode (I want to use it this way)

“Add-on mode uses the Jellyfin server to translate media files from the filesystem to Kodi. This is the default setting for the add-on, and is sufficient for most use cases.”
So this leads me to believe that if I use the add-on this way I DON’T have to manually mount all my server sources over NFS or SMB. This is what I want since Samba is my bottleneck on my current setup before Jellyfin.
But when I set things up this way, Kodi complains that it can’t find my media… Am I missing something?