"We were wondering if the Oregon Grape that is used as an ingredient in Tripsy is OK for the Kidney because our vet was concerned that grapes can cause damage to the kidney?"
You are right to be wary about products with grapes as they are toxic to dogs. Oregon Grape is safe for pet consumption though, as it is not related to grapes, but only gets its name from the purple berries it produces. In herbal remedies it is also the root that is commonly used. The only pet warnings for Oregon Grape is that it is not recommended for use in diabetic animals.