That dog reaction is the part that gets me honestly. Animals pick up on things way before we do, and when they fixate like that - just locked on one spot and won't move - something is definitely off.
I live out in the Appalachians and we get all sorts of wildlife up on the roof, raccoons, squirrels, you name it. But theres a difference between the sound of an animal scrambling around and something that moves with more... weight to it I guess. Did it sound like it was walking in a pattern or more random movement?
The Mothman sightings around here often get reported alongside weird animal behaviour, dogs refusing to enter rooms, cattle acting up, that sort of thing. Not saying thats what this is but the combination of roof sounds plus a dog staring at the ceiling is the kind of thing worth paying attention to.
Did anything else happen that night? Power flicker, strange smell, anything like that? Would help narrow it down a bit.