Well, that's just a bit close to scaremongering
Yes, Chicken Soup is made by Diamond. Actually, Schell & Kampeter Inc (owners of the diamond label) make a good dozen or more different dog foods. But they also make them in different places, and with different ingredients. Chicken Soup happens to be made in an entirely different plant, in a different State to the affected foods. And it doesn't even contain any of the affected ingredients... The only relationship it has to the affected foods is it's owner.
Since the aflatoxin originated from infected corn, I'd personally be far more worried about buying a food with corn in it than I would about buying a food
without corn but made by diamond. Thing is, other manufacturers may have bought corn from the same producer
That doesn't mean I wouldn't watch closely for any signs of illness. Sure, I would. But I'd be doing that with any dry dog food. Most especially any containing corn.