The Lowe tune turns out to have been a red herring. Do, if you have the opportunity, listen to the sound sample I indicated; you are much more likely to recognise the tune actually used, if it's a borrowed one, than I am.

It would be no great surprise if the verses were to turn out to be a fabrication based on a few genuine lines, and which has simply been assumed all to derive from the trial transcriptions because part of it does. Thanks for those references. A look at the piece in Chambers seems necessary, but unfortunately the only runs available where I am are 19th century.