Those three, along with Seattle, are a bit of a stretch, but they are around 200 km away from the Rocky Mountains if you use the largest defined area for said mountains.
It is close enough to meet the requirements for my quiz, although I made this quiz four years ago and it would have had vastly different standards if I'd made it today.
There is no problem at all! Anyways your quiz seems quite different to mine (and even if it was more similar it's all fine, after all most quiz ideas have been done before, at some point). Your quiz looks real interesting, I think I'll go try it in a moment.
The list is nowhere near complete. If I were to revamp it I don't believe many of the cities on the quiz would belong at all. Vancouver, Victoria and Seattle should be removed, I think Kamloops doesn't belong either, while Fort Collins and Prince George could be added, amongst others.
Calgary and Denver are probably the 'archetypal Rocky Mountain cities'.
Calgary and Denver are probably the 'archetypal Rocky Mountain cities'.