The idea of Leadbelly having a publisher he would drop in and offer songs to is a great story.
Of course, examination of sheet music of his songs tends to suggest he only wrote a third of each song, the rest being created by two very talented folklorists.
Wolfe & Lornell's biography suggests he would have sung the song with Blind Lemon Jefferson in the streets of Dallas in 1912. He may well have made it, and certainly did the remake about the liner Queen Mary. (I in a thread a while ago suggested that the latter song only existed on an acetate in ETSU archives, but is mentioned in the biog - I've just noticed this and have just skimmed through the discography without seeing where else it may be recorded.)