I am sure that shantymen would extemporise so there would not be a definitive version.

Most that I have heard differ between the first and third lines of each verse.

Boney was a warrior
A warrior a terrier

Boney beat the Prussians
The Austrians and Russians

Boney went to Waterloo
Met the boy who put him through

He met the Duke of Wellington
Then his downfall was begone

I used to know several other verses but haven't sung it for over 25 years and the senior moments are becoming senior half hours