I wouldn't touch it. I had three sick dogs on exactly that food. Many people had sick dogs on that food. There is much better out there for the same price.
Hmm, I will see how it goes. If it doesn't agree, we can get a refund and a free bag of new food.
Are you sure they didn't just get sick because of the transition of foods? There usually is a bit of an upset digestive system after any abrupt change in diet.