Lateral motion doesn't affect vertical motion unless air resistance comes into play, they're both going to be pulled down at the same acceleration from the same height. Canada isn't going to be kicked up either, just forward
On the other hand, Canada is falling face first, and the US is tumbling backwards, so they'll probably fall slower
These are interesting physics questions that should never be experimented with Canadians. Perhaps Trump and shifty Shift can be put on the see saw. I expect a slight edge in downward momentum for the Canadian, as there would be a small see saw up for the American before their fall starts.