You cannot use observed animal responses to somehow presume to know the state of their inner mind. As you have previously concluded in past postings, responses in a material brain will be predetermined by subconscious brain activity before they kick in to conscious awareness, which leads to the conclusion that such responses cannot be used to indicate the state of conscious awareness.
If I hit my finger with a hammer, I suffer pain, and I am aware of this because I am conscious. Observation of my responses would be evidence to the observer that I feel pain. If I am unconscious, I am not aware and I do not feel any pain. Observation would show no response at all.
Similarly it would seem a dog would feel pain if it were conscious, and likewise we would see pain responses in the animal. If the animal were unconscious, observation would show no response at all.
As we have a great deal of evidence for a dog's nervous system and brain activity, just as we have for humans, then it is surely sensible to suggest that the dog would also be aware of the pain. Hence it is conscious also.
If we go down your path, which suggests that we cannot use observed animal responses to somehow presume to know the state of their inner mind then this must remain true for all human beings(apart from yourself) also.