I think that Dill could just be claiming he wrote the song, which was a common practice for people who recorded certain folk songs after they became famous. I heard somewhere that after the Carter Family made "Worried Man Blues" famous, there were about 5 or 6 different copyright claims (including one from A.P. Carter himself).

Let's focus on the woman in the black veil for a moment. I've always thought of her as the best friend's wife. At the hanging, she "sheds not a tear" (in my opinion to keep up the facade) yet some nights she visits the dead man's grave wearing a long black veil which is a traditional sign of deep mourning. It also said that she cries during these visits. This all leads me to believe that she is unhappy with her marriage to the best friend and she really was in love with the man who is now dead. Now I don't think that the husband is the real killer because framing his best friend for the crime is too complicated. He would have simply killed either his wife, his best friend, or both.

Check out the tense changes in the last verse...kind of odd. The first two lines talk as if he's standing on the scafold looking out into the crowd but then he says that sometimes this woman visits his already burried body. What do you all make of that?