A death certificate for who appears to be the same John Dickson casts doubt on the possibility of a match as a child of Robert & Isabella Dickson.
The death record states John A. Dickson died 5 March 1940 at Canton, Stark, Ohio, residence Magnolia, Ohio, age 54 yrs 3 mos 3 days, born 2 Dec 1885 in ND, spouse Viola Dickson, father Thomas Andrew Dickson b. Scotland, mother Alice Piatt b. Canada.(The 1930 census indicates this John & Viola married in about 1928 so if it's the same man his 1st wife, Veronica, may have died 1920-1928.)
The birthdate and birthplace match the John Andrew Dickson who married Veronica "Vernie" Sliwinski in Toledo in 1915, however, his parents are listed in the marriage record as "Robert" Dickson, not Thomas, and "Belle Moffett", instead of Alice Piatt. Perhaps the informant (his 2nd wife Viola?) for the death certificate was simply mistaken about the names of John's parents but it certainly raises some questions.