When asked, his answer took me a little by surprise knowing the scope and aim of his collection.
"Lonnie Johnson's 1948 King recording of Tomorrow Night would be my island record" he said.
I quickly typed a search for other versions of the song...such as LaVern Baker's or Horace Heidt's...and unbeknownst to both of us, we discovered that Johnson actually recorded the song with piano and bass accompaniment a year earlier in Detroit for a small R&B label."
My friend found a lone copy on ebay that evening and promptly purchased it.
Lonnie Johnson g, v / unknown sb & p.
Recorded in Detroit in 1947.
Here's the flip side for completeness.