If you felt that the featured article was weaseling, here is one with less ambiguous wording. They isolated 24 tonnes of contaminated dust, 70 personnel took blood tests.
It is my understanding that there are radiation detectors at the entrances to recycling furnaces (as well as elsewhere in the US transportation-chain) for just this purpose.
Well this is telling you to have any metals that have been passed though Thailand ran under a geiger counter. At least in the US any major recyclers perform this operation to prevent radioactive materials showing up in the product stream.
Initial reports seemed to suggest it was found before it was smelted but that is not the case.