For the story of Maynard, I suggest you wait for the book, He did write other cowboy songs, but they were not "hits" in the way that Tom Sherman's bar-room was. He certainly never made any money from the song.

I have posted Thorp's 1908 version, with notes from the Fifes, of "The Cow Boys Lament" in thread 3918: Cow Boys Lament
It is quite different from the cobbled together Lomax version. Note- In 1921, Thorp adopted the Lomax bowdlerization.