Never had any trouble singing it when I was a student. Of course, the lyrics we sang around the campfire are only found in collections such as the Randolph-Legman "Roll Me In Your Arms." The best in those volumes is close to "Red Wing (3) in the DT.
Here are the two last verses from this version as sung by Sam Eskin.

Now when she came to life, sshe seized a Bowie knife,
And with one foul pass cut his balls from his ass,
And now this cowboy's roving days are past.

Oh, the moon shines tonight on pretty Red Wing,
As she lies snoring, there hangs a warning,
A cowboy's balls her tent adorning,
Pinned to the flaps of- Red Wing's teepee.

Randolph-Legman, Roll Me in Your Arms, p. 568-569.