Kennard would meet Wood's description, I think, though it isn't the book. The mystery of what book Wood saw clearly remains.

I may regret saying this in the future, but I think this very well could be the book.

I have been working with the expectation that there is no text very similar to "Wellerman" in any book. Rather, such verse as "Along the coast the Magnet came" was taken as inspiration for writing "Wellerman," using the AAAB form/meter.

Among the main arguments for that are, in my mind:
1) The pretty distinctive form/meter
2) The "fact" that nearly all of the language in "Wellerman" sounds modern/ newly contrived to me
3) "Magnet" was in multiple sources and, so far as I've seen, there was not much else to show for New Zealand whaling verse/song.
Plus,
4) The Kennard book mostly fits Tommy Wood's description. To add: He said it contained poems. Each chapter of the Kennard book begins with a 4-line (AABB) stanza.

Arguments against that in my mind are:
1) Even if the form/meter is distinctive, there appear to have been a few parodies in that form endemic to the area and "Wellerman" could have been yet another parody—making the correspondence with "Magnet" a coincidence.
2) There are some fragmentary text correspondences to "Golden Vanity" that feel like they would have been in the original—even if the majority of the remaining lyrics were made up. I'd expect to see those in "Magnet," but they aren't there. Though it's possible C also cross-reference "Golden Vanity."
3) Tommy Wood's quote says, "The Wellerman was an actual poem in the book but not quite in rhyme I had to adjust some of the words to fit the tune..." "Magnet" does have a "flaw" in rhyme in the fourth stanza. Otherwise, however, "Magnet" --> "Wellerman" is much more than "adjust some of the words."
Plus
4) The Kennard book does have ~4 photos—I'm referring to Wood's description—but they are not of ships. (They are photos of Kennard in the early 1930s.)

My mind talks back to the "against" arguments by rationalizing: There are probably errors in Tommy Wood's memory, so some elements of his description are likely red herrings. He could be hallucinating that the illustrations in the book were of ships, or not being totally genuine about the degree to which the poem was transformed to become "Wellerman." This is not a slight to Tommy Wood— I'd expect my own recollection after so many years to be even more sketchy.

I'm more of a hopeless skeptic as opposed to a hopeless romantic.