Huawei arrest circus could maybe have been avoided

Pretty much everybody else has weighed in on the on going circus around the arrest in Vancouver of Huawei CEO Meng Wanzhou, and the subsequent retaliatory arrests of Canadian citizens Michael Kovrig and Michael Spavor in China, so I guess I may as well add in my own twopenn'orth.
I was initially amazed that Canada was obliged to arrest and extradite anyone the US wants to target at the drop of a hat, but apparently that is exactly what mutual extradition treaties are all about. The proviso is, though, that the crime in question must be one that both countries recognize. So, is there no argument to be made that, although the USA (since Donald Trump's recent policy change) has a policy of sanctions against Iran, Canada (along with most other major countries in the Joint Comprehensive Plan of Action) has no such sanctions or beliefs, and so Canada is under no obligation to arrest or extradite anyone on such grounds? But it seems like the US has pre-empted that argument and ensured that Ms. Meng is being accused not of breaking US sanctions but of fraud in lying about the Iranian business dealings of a Huawei-connected company. So, no go there.
What does seem to be the case, though, is that the Canadian government has perhaps been a bit naive in not looking for what what ex-Chrétien advisor John Manley calls "creative incompetence". Prime Minister Justin Trudeau apparently was informed of the arrest plan well in advance of Ms. Meng's transit through Canada, and it would not have been difficult to arrange for a strategic warning to be sent to the Huawei contingent. This would not strictly have been in contravention of the extradition treaty but it would have avoided the mess that Canada now finds itself in with respect to the blow-hard Chinese government, which has, as usual, reacted poorly to the provocation. An article by legal scholar Michael Byers describes the example of the creative incompetence.of the British government in the arrest of Chilean ex-dictator Augusto Pinochet in the late 1990s, and explains how the Meng case would have been a much easier exercise, both practically and morally.
Anyway, that moment is past, and Canada is already in deep doo-doo with China. Trump, as usual, has made things worse for everyone by admitting that his plan (probably all along) is to use Ms. Meng as a bargaining chip in the US's trade negotiations with China. Unfortunately, Chinese President Xi Jinping also needs a trade treaty, and he will probably have a sneaking respect for Trump's tactics. So, China will probably take out it's frustrations on Canada, and go easy on the Americans. It all seems so unfair.