Hello again.
I do hope this information is of use to any interested party.

I have now found the book that sourced most of my lyric.
It is 'Tales from West Yorkshire' by Leonard Markham,
first published by Countryside Books (Newbury, Berkshire) in 1992, reprinted 2001, ISBN 1 85306 190 5.
I surmise from the extensive bibliography at the back of the book that Mr Markham's own research would have been gleaned from the 'History of Spen Valley' (Douglas Hird 1985), 'Annals of Yorkshire' (John Mayhall 1862), 'Yorkshire Oddities, Incidents & Strange Events' (S Baring Gould 1874) and 'Legendary Yorkshire' (Frederick Ross 1872)

The relevant paragraph (word for word ) from my source book reads as follows….

'Cartwright offered evidence which lead to the arrest of William Hall and sixteen of his followers,
and with obscene alacrity, the accused were tried, convicted and publicly hanged.'

So my line…

'William Hall and sixteen more were tried and they were hung'

…not only fits my melody snugly, but has been obtained from what I consider to be a bone fide source.
Therefore, for now, I would prefer not to have my work deemed 'wrong'.

My own memory does seem to have failed (again!) in the belief I might have pulled the line in question word for word from the text.
I now remember being glad it just didn't simply say…
'Seventeen were….' for happily, by isolating William Hall in the text, the author helped me make it 'scan'.

I will stick with my lyric as written, though I will not claim my source is the definitive one.
I am always willing to 'correct' my work when necessary and may yet do so if ever convinced there is a more authoritative source.
That OK with everyone? – Cheers - HFA