Welcome Marg; it is stories like yours that bring these songs to life, and I would love to know more about your great-uncles. I've already quoted above the sparse biographical information about Emerson Woodcock given in the LP notes.
Sadly that LP has been deleted, and is unlikely to be reissued anytime soon.
However Edith Fowke did record some other songs by Emerson for Folkways, and these are still available from Smithsonian Folkways Recordings who will make up a CD for you from the original 1961 LP "Lumbering Songs from the Ontario Shanties" FW04052

I believe that the University of Calgary has some of Edith Fowke's material, but I'm not sure whether this includes copies of her field recordings in Ontario. I haven't been able to find anything yet about Dr Pollack.

Hopefully somebody else here with some knowledge of Canadian resources will be able to help you. Good luck.