The politically-easiest choice may be spending a year or two in a Canadian prison, over literally nothing. This would manage to allow Canada to neither turn them over to the US nor China immediately, while ensuring at least a degree of regime change before any risk of further question. It skips in cowardly fashion all the political questions.
So, it is at least a different option.
The Eastern District of New York is mostly known for shitty human rights violations in campaigns targeting "pedophiles." The city of new york, on the other hand, is mostly known for targeting the LGBT community. It should be very easy to start a lot of shit on that city on the latter basis.
I looked it up; sadly, Viktor Bout was indicted in the southern district of New York, which is otherwise less-infamous. They were indicted as part of a loyalty test for a far-right terrorist organization, however, and in fact they "failed" (or succeeded, depending on how you feel) by dealing with the FARC. China is on record as opposing the recent violence in venezuela...
...by which it could easily be argued that the charges are wholly political and mostly based on a criminal war of aggression in south and central america on the international stage. (and Venezuela is currently harboring the dissident, and far more legitimate, wing of the FARC).
Perhaps someone with more research resources could link the districts of Eastern and Southern New York and make an even stronger case of partisanship, not to the administration, but to a transnational criminal network known for terrorist activity. One would want one's case to be legitimate, but I'm sure someone gets coffee with their peers across departments, especially in the same city. I'm also fairly certain that the Eastern district's shenanigans don't come out of thin air; I was rather surprised to see the southern district.
Meanwhile, the trade battle over 5G backbone development allows appealing to the WTO in writing this whole thing off, apparently rightly, as an "unfair trade practice by the United States."
All of this, of course, is largely a setup for asylum. Effectively, the US is a politically and economically, but not legally, motivated actor in this matter.
At the same time, one has the concurrent example of the nonprosecution of the bank executives who created the 2008 financial collapse - who are on record as having done so deliberately in a racketeering scheme to implement racial segregation. That's a whole mass of several charges, and as such, implies equal protection before the law issues; the absence of a fair trial can be well established by the equal protection issue, and there are likely other examples. As such, no legal extradition can be had.
The peasantry, on the other hand...
...might want to ask internationally after canada's former ambassador. Poor guy should get his job back.
These are the initial impressions. There's at least half a dozen reasons why asylum (and nonextradition) would be legitimate, and multiple angles for international appeal. Meanwhile, one can run down the clock on at-least-partial regime change.
This also makes it in huawei's best interests to make sure that the democratic party does not, in fact, merely flat-out-throw the election... again. At least a mild threat of regime change on election is required, something the democratic face of the uniparty is threatening not to do.