The permits are issued to people. The dog is not a person nor a pet even. You can't require the owner to have for an architectural issue. Now, the AB was passed in 1968 and many of the shelters renovated. If there is not enough space to accommodate a person with a disability they would probably need to fix it. The NPS should have taken the law into account at renovation. I'm not suggesting they haven't. They have camping shelter rules but specific sleeping space requirements I don't know. Like do they have to offer a larger space. What magic formula is used for deciding shelter capacity in the first place I don't know. If it was a problem they could just reduce it to 7.