Good quiz! One clarification for the Stanley Cup question - although Vancouver has no Cup wins under the NHL banner (they took possession of the Cup in '25/'26), the Vancouver Millionaires professional team did win the trophy in 1915. I would advise changing the question to focus on NHL teams.
Not that it matters since Johnny Cash did do a non-single version of the song, but the biggest/first hit version of "I've Been Everywhere" was by Hank Snow, a Canadian-born country musician. He was not born in Toronto, Vancouver, or Montreal, though.
Technically, Toronto also has a system like Vancouver's SkyTrain but its not called the SkyTrain. Also, if you are counting city proper, Montreal is the only one located on an island. However, metro Vancouver and Toronto do contain islands with a good section of metro Vancouver on an island. Otherwise, great quiz. Would like to see more Canadian quizzes featured.
Source: https://www.nhl.com/news/nhl-stanley-cup-champions-winners-complete-list/c-287705398?tid=287709666
Sydney, Melbourne, or Brisbane?