When was the last shot he had? The @%$#!! pharmaceutical companies are putting aluminum in the medicine that is injected! It is as bad or worse as mercury, which I believe they are still using. You can get shots, that don't have that crap in it. Ask your vet. Also ask if dogs can take Coconut oil. If you can, start giving him the organic coconut oil, that is cold pressed, not boiled. They are finding out, more, and more benefits of coconut oil. One is the aid in healing brain tissue, and nerve problems. It is also good for Alzheimer patients, as it slows the progress of the disease, and in some patients, can actually reverse the effects. It is worth a try. He is a fine looking fellow, I think he is worth the effort. I also see that he answered your question, of inside, or outside. With the seizure incident, I would definitely say inside. Good for you, adopting an older animal.
Wayne