I have several of those versions, (plus a version by Andrew Calhoun I could email to someone..)

This is not a frequently seen song, and as with other songs of this nature, some singers have worked on their own to adapt and create a decent version in order to sing it. I think I hear tunes 'borrowed' from other ballads, as well as thematic similarities. It may be pretty hard to trace exactly how it is gaining new life.