I have nothing concrete to add to this question except to say that finding songs in oral tradition around the time of Foster does NOT prove they antedate Foster. . . kinda like when Patrick Gilmore "wrote" When Johnny Comes Marching Home Again-- and 100 years later the Clancy Bros were singing Johnny I hardly knew ye-- but there were no written records on which to prove which came first! never did see that one get settled either! it comes to the Scottish verdict, "Not proven" Pete