A person on bladeforums gave me the contact for the head of the trade guild for Puuko knifemakers. I sent him a note asking about the man in the movie. He sent this reply. fwiw - I used google translate which is pretty amazing.
The man is Kustaa Lammi (1901-2001). In this movie he is about 75-80 years old. I knew very well a man and we were friends. I teach myself the same knife, 66 colleges in Finland. I've written a book Sorkoupotus manufacture these knives. I put a picture when I find it on my computer.