GUEST.CJB: I wonder if they know the term ‘tounguers.’

If you are referring to the New Zealand whalers, the term was known in New Zealand. Elizabeth & Harry Orsman, The New Zealand Dictionary, second edition, New House Publishers, Auckland, 1995, p. 294 (note the spelling):

tonguer 1. (whaling) Hist. One who, for his work of cutting in whales or abandoned whale carcasses or parts of them, receives the oil of the tongue (also of other parts) in payment.

The second definition is for workers in a "freezing works."

In an interesting sidelight on the question of origins, neither of my dictionaries of Australian English include the term, although that might be because they consider it generic English.

On the flip side: Song of a Young Country has another song, "Come All You Tonguers." This was first printed by Bailey & Roth. And the source was... John Leebrick, the source of "Davy Lowston."