Then he contacted the author of the book I had just listened to, David Fulmer, who called me as well! And David Fulmer provided me the correct name of the song that Jelly Roll Morton (as portrayed so memorably by Dion Graham) sings in Chasing the Devil's Tail. It's "Winin' Boy." And I think you can listen to Jelly Roll sing it here (scroll down to the end of "Solo Discography") or watch a record revolve on a turntable. And here are the lyrics (think raunchy!).
I've ILL'd another book read by Dion Graham, as he gave me some more titles from his bibliography/discography. Can't wait!