Unfortunately "ask a lancastrian, Mike Harding" isn't always reliable. He blatantly mangles a few lyrics in his book "Folk Songs of Lancashire" to fit his own sensibilities. In the notes for "The Collier Lass", for example, he says "I have missed the last verse out because it is boring". Presumably, MH preferred Polly Parker to remain in penury and in "the greatest of dangers" down the mine rather than sensibly marrying the chap she'd set her sights on for a better and safer life above ground...

As Rawtenstall Annual Fair was written by Weston and Lee there should presumably be some original sheets around somewhere to settle things conclusively. I've certainly usually heard "Odsall Bottom" sung mostly here in Lancashire and that's what's recorded on Topic's "Deep Lancashire" by Lee Nicholson and more recently by the Bolton Bullfrog, Bernard Wrigley.