I don't believe the US is doing it, essentially I'm doubting the specific facts you presented i.e. a warrant since Aug but no arrest until now, for political reasons.

One of the reasons I doubt this is because Trump does not control or direct these orgs - they are not highly politicized.

And also ... why would the US create some kind of warrant/indictment to not have her grabbed?

Maybe you are right, but I actually don't think any of it makes sense. Trump gains nothing by having someone nabbed like that.

Chinese nabbing of Canadians I do however think is political.