Irwin Chusid is to outsider music as Irving Azoff was to Atlantic Records. This is to say that Chusid is the outsider music mogul. He's the guy behind the guy behind the artist… that you've probably never heard of.
However, you're familiar with Chusid and some of the artist's work he champions.
You may not know who Raymond Scott is, but if you're above a certain age, you may recall the animated series The Ren & Stimpy Show. Well, it's Chusid's dogged championing of Scott's music and push for its re-release that found its way into the earholes of The Ren & Stimpy Show Creator John Kricfalusi and Creative Director Bob Camp.
Links 
Outsider Music
Harry Smith 
Songs in the Key of Z by Irwin Chusid
Sun Ra: Art on Saturn: The Album Cover Art of Sun Ra’s Saturn Label (October 2022) Sun Ra, Irwin Chusid, Chris Reisman
The Carl Stalling Project
That’s All Folks by Steve Schneider
Raymond Scott
The Ren & Stimpy Show
Juan Garcia Esquivel (Esquivel!)
The Langly School Music Project
WFMU
Lucia Pamela
The Shaggs
Wesley Willis 
Jandak