JK, I'm sorry PickupExcitations didn't respond to your solving the mystery (which I find absolutely mystifying... I mean why would you make a post like that and then not thank the person who figured it out? Perhaps there is an innocent explanation - I was on my phone when I first read your answer, and I can't easily sign in and post that way, for example!) Anyways, I for one appreciated seeing you solve this little mystery, and I hope you would consider reinstating your answer for posterity's sake. I definitely enjoyed watching the clip from the documentary you shared and hearing Darian's little acid trip remix of California Girls!
Now that’s more like it! Of course I'll reinstate it. I should add that I've been enjoying your discussions with the famous Julia, who has given Smiley the shake-up it sorely needed.
1)
"In the documentary
Beautiful Dreamer: Brian Wilson and the Story of Smile [Brian] says, 'I always wanted to learn about life, metaphysics, spirituality, philosophy.'"
Source:
https://laelarrington.com/2015/07/beach-boys-love-and-mercy-movie-and-the-lost-gospel-of-brian-wilson/Maybe the music accompanying that scene holds the key. Just a thought...
2)
Here you go. From 8:47 to 9:38, you can hear a trippy version of the intro to "California Girls". I'd say this is the mystery track -- the image just after 9:05 would seem to bear this out.
https://www.youtube.com/watch?v=0SriaRRcA6w