I've heard a recording of Jim Morrison in a studio in France with some street teens (who seem drunk) playing. I think it is supposed to be from 2 weeks before his death.
Some American Prayer type poetry and vocal fragments (sometimes with limited instrumentation behind them). The sort of recordings that are easy to add new music to.
I'm just curious if this "lost song" is what this is.
That's kind of what I was wondering. Jim also filmed a short movie that went with one of his poems, as well as some videos for certain songs which are available (like "L.A. Woman"), and I'd guess there are some other videos which may be extant.