I don't think you are understanding what an extradition treaty is or how it works. If you commit a crime in Canada, then flee to the US the US will hand you over. CITIZENSHIP is a huge deal in these, and often times countries argue who will be the country to hear the case. Not only that, both countries have to agree it is a crime.
Ya know what, I'm getting tired of explaining this overly optimistic stretching to get the loosest definition of a crime that would require multiple major hurdles to be cleared before even getting to the part where you have to meet the absurdly high standard of proving beyond a reasonable doubt. If you legit think Canada is gonna try and prosecute a US citizen for actions taken in the US because it effected a Canadian citizen who has no one pressing charges or pressuring the Canadian legal system to lock charge in to the US and lock Zoe up as a Murderer, go ahead. Its gay as fuck but continually trying to explain that this isn't how the world works, only to have a brand new stretched out explaination trotted out is exhausting. I think I give Absolved Mediocrity a pass cause he dug the evidence himself, contacted Canadian police himself, and is willing to take even a strong condemnation by the mounties if there is no actionable charges and is fully aware that nothing might happen from any of it. I may disagree, but he's putting in the work and I can admire that.
I just wish I saw less people cherry picking things that they think will give them the result they want because they think if they say it enough it will become true. It reminds me of how Reddit in 2016 thought of any excuse and way possible to think of a way Bernie Sanders could become president.
I also find it weird many of the people chanting lock her up with Zoe don't wanna report her patreon which is reportable via their own TOS (and you have proof of future potential victims with her list of guys she wants to bury). If its all or nothing, then don't cry about getting nothing.
Here is a documentary that covers a very famous extradition case for an actual provable murder. It should give you an idea how tall an order you are asking.