The food import issues came into law back when I was importing, and distributing food here in Canada. At that time one of the head Canadian Food Inspection Agency (CFIA) managers in Canada told me that in order to get any Asian made pet food into Canada that for a starter, the facility need to be inspected by the CFIA. Failure to comply resulted in being banned from Canada. Of course there was still black market imports taking place, from small time non tax paying online sellers, to companies that would cross the US/Canada border, and buy from some of the larger distributors in the US, such as Royal on the East Coast. I posted about that issue in the past thread.
https://www.monsterfishkeepers.com/forums/threads/canadian-food-inspection-regs.306445/
The problem with Asian made products, is they often don't have the same standards as we do in North America. I'm sure that you are well aware of that, so what's in some pets foods made in countries such as China, is anyone's guess. I believe that the melamine fiasco resulted in the factory responsible in China (or at least the one caught) being closed down, and the person running the factory being hung, or shot. At least that's what I read years ago.