Only useful if the person giving the information knew it. She has said that her father has very little information about his mother. The marriage record will be better as she would have filled it out herself.
In the 1940 Voters' List, there is a Joe Madl (and wife), a furrier, living at 178 Lippincott Street, Toronto. Given the profession, I would suggest that these are George's parents. In 1945, they are identified as Joe & Elizabeth Madl, living at 70 Annette Street, Toronto.
In 1949, adult children, Christine & George, are living with them. By 1953, at 31 Cliveden Avenue, George is the head of the household, and living with him are Mrs. Peggy Madl, Christina Madl, Joe Madl and Elizabeth Madl. This narrows down their marriage to between 1949 and 1953 almost certainly in Toronto.https://www.orgforms.gov.on.ca/eForms/start.do
You want to ask for a certified copy of the marriage registration which will have all of the information. I believe they will do a three-year search.
Elizabeth arrived in Canada with children, Anna, Kristina, and Gyorgy (George) aboard the Marloch in May 1927, from Magyarpolany, Hungary; they were bound for her husband, Joseph, in Butler, Manitoba, who had arrived in Canada a year earlier. George was only 8 months old at the time.