I don't understand why poison control told you this.

We had a dog come into the clinic a couple of weeks ago coughing up mucousy blood. The owners had fed him chicken bones the night before ( ) so they thought he was choking. We took xrays and his lungs were full of blood. It turned out he had eated 2 bars of rat poison a week before. Rat poison causes death by internal bleeding, but because he was a big dog, it metabolized much slower than it would in a rat.

I would still take him to the vet. Poisoning is a serious thing.