Apparently the version from Willie Reilly also discloses the palmer's true identity in this variant:

(Stanza 5) 'Oh, for I am the Lord that rules on high; '
Green grows the lily-O ;
'Oh, I am the Lord that rules on high; '
In the well below the valley-O .

(Stanza 6) 'Oh for if you're the Lord that rules on high ...
Oh the Lord may save my soul from Hell.'

This and some of the other information from McCabe, Mary Diane (1980). "A critical study of some traditional religious ballads." M.A. Thesis, University of Durham, 471 pp. Available at http://etheses.dur.ac.uk/7804/1/7804_4801.PDF