3) Simon Daunais and Genevieve Guertin are indeed Simon's parents.
4) I know nothing about Joseph Masseaux. Certainly not aname found in Québec. I would say the correct spelling is Mousseau, a family of the Joliette area. There were a few Joseph Mousseau there at that time.
5) Since the parrish registers in Quebec are almost complete for the priod that you search, I would suggest that you look at them and not in the census. However, it would take a clue to limit your explorations.
6) for details about Josephine's parents, please email at my personal address.