I have to correct myself. Ciarán Ó Geallbháin wrote to me that Labhrás knew both Irish and English verses about William Crotty. He doesn't know how close Labhrás' words were to those which Ciarán got from Nioclás Mac Craith. So we can't say that the English lyrics are a translation of the song as sung by Labhrás, only that (as I originally said) they are quite close in meaning to the English verses.