I recently extended a cordial invitation for demons to visit my home. Not a one showed up. I have a parakeet (shocker!), and she showed no signs of being possessed.
Although ... she does bite my fingers when I'm typing on the computer; she goes berserk when she sees a presciption pill bottle and attacks it with impressive ferocity for a 2-ounce bird; and, most unnerving, when she stands on my floral kitchen mat, she blends in so well, she seems to disappear altogether, like a wraith in the fog.
Of course, she did all of these things before the demon invitation, during the demon invitation, and after the demon invitation. So I think your dog is safe.