It's an interesting enough theory... The fact that he uses phrases like "Far away across the field" do lend some credence to the notion that it's tied to African-American folklore, but still, beyond that I think the connections are pretty slim.

You'll also note the the crossroads, as a figure in African-American folklore, is associated with Jesus as often as it is Satan -- in the classic Robert Johnson song, it's Jesus who approaches him at the crossroads, not the devil. This mixture comes from the fact that the archetypal deity associated with the crossroads in african culture (Elegua, Esu, Legba) did not easily fit into Western duality -- a wise figure, who could also be a tricky figure, who could be dangerous or enlightening, and so forth... "Where others see their targets, divine symmetry" and all that: In keeping with Water's non-binary belief system of the time.

All the same, I think he was probably just on drugs, trying to write a children's story.