It turns out Manly Wade Wellman's entire "John the Balladeer" is available in full text on-line.
And a direct link to the story "Vandy Vandy."

Now having read the story, I wonder if there's a clue if we could track down the the peculiar version of "Wife of Usher's Well" used in "Vandy Vandy":

There was a fair and blooming wife
And of children she had three.
She sent them away to Northern school
To study gramaree.

But the King's men came upon that school,
And when sword and rope had done,
Of the children three she sent away,
Returned to her but one. . . .

--Charlie Baum