G'day again MMario,
I don't know from which sheet music you copied the words, but I just looked back to the place where the song first came to public attention - at least in the folk revival that was about to happen. The song was a favourite in Reedy River, Dick Diamond's 1953 play about the aftermath of the great Shearers' Strike of 1891.
In the accompanying song book the note says " This version was collected from a shearer in Melbourne, and after it had been used in "Reedy River" for some time, the original published work by Edward Harrington to Roy Jeffries' tune was discovered.
The credits are then given as:
Words: Edward Harrington. Music. Traditional
Maybe there is a set of collected words where the unnamed 'shearer' gets it wrong, but Harrington followed the rhyme scheme I have noted... and that is how I sing it.