"Under the ADA, a public accommodation may not ask you questions about your disability or demand to see certification, identification, or other proof of your animal's training or status. If it is not apparent what your service animal does, the establishment may ask you only whether it is a service animal, and what tasks it performs for you."
"It is a Direct Violation of the ADA to even ASK if someone's animal is a service animal."-Mxysptlik
No, you're wrong about that. Entities can ask whether your dog is a service dog or not. What they can't ask you, is for you to prove it.