That’s a possibility, Tiger, but the more I think about it, the more I am of the opinion that it was probably the work of an unofficial sub-contractor hired by a greedy plant manager.
They did a pretty impressive overview of the plant where the gyoza came from on one of the Japanese television stations. The sanitation procedures for the workers were impressive, the plant itself was immaculate, the process efficient from start to finish — all of which is expensive as hell.
Now if I was a greedy unscrupulous plant manager and I was tasked with delivering say 1,000 metric tons of gyoza in a certain month at $1,500 per ton and I had made a deal with an el-cheapo plant across town for five tons at $500 per ton, I could arrange to sneak those into the packaging line during an off shift.
It would take the connivance of some other staffers, but they are greedy too (this is China we’re talking about) and walk away with a healthy profit.
And of course the unofficial subcontractor has none of the impressive (and expensive) sanitation measures, quality ingredients, etc.
I know that scams like this exist because they have been exposed before. In fact, I would be willing to bet money that it happens and goes undetected quite often, because in most cases the subcontractor is careful enough to make the product good enough to pass casual inspection and the plant manager knows damn well that only a small portion of any shipment is actually subjected to thorough testing.
The only reason they got caught this time is because people actually got sick. If the pesticide dosage had been slightly less, no one would have been the wiser.
In any case, it just reinforces my decision not to buy anything from China if I can help it at all. Taiwanese products are fine.
Still unofficial subcontracting is also a highly possible scenario.