As far as we know, the family (his wife) was informed as soon as he went he went missing: he never returned from Dublin on the boat he was meant to. The story in the family is "it was about the time of the Easter uprising", so I suppose strictly there is not necessarily a formal link between the two, it's always been an assumption.
1911 census they are listed at 320 Woodhouse Lane, Liverpool, and John Dickinson (who went missing) is listed as a colliery surface manager.
Margaret Alice died 29 June 1936 at 9 Claughton Drive, Birkenhead.
Hoping mystery can be solved