After twenty four hours of working with the plug in, I can get a gallery inserted and remove file sharing by installing a different version of the jwplayer.
But it no longer seems to recognize new self hosted videos using (plug in) Add From Server. In "Gallery Details" if I "Scan Gallery Folder", what folder is it scanning? Shouldn't I be able to set that in the "gallery settings"?
I also can't create previews using ffmpeg, but I'm new to ffmpeg so investigating it with my provider that it's installed on my server, so that might get resolved on its own.
The plug in has great potential, but sadly it's currently not working for me. I might have to abandon it for another solution.