Sorry....I find no Gertrude Johnson, born 3 Oct 1907, in the SS Death Index that might give a clue as to where she was from.
Nineteen females named Gertrude in SS Death Index born on 3 Oct 1907.
The following Gertrude Nowak's in 1920 US Federal Census and where they were living in 1920 and where they were born, which does not mean any of them are her or married a Howard Johnson and no Gertrude Johnson found in the 1930 record with a husband named Howard.
Gertrude Nowak, Detroit Ward 11, Wayne, Michigan abt 1907 Michigan
Gertrude Nowak, Detroit Ward 14, Wayne, Michigan abt 1906 Michigan
Gertrude Nowak, Ardsley, Westchester, New York abt 1908 New York