Protozombies need support too. Compliment their dog. Let them know you support them, at least as long as they’re not slurry and shuffly. We all may be slurry and shuffly someday.
P.S. If you encounter these people in a bar, you should let a little of the slurry and shuffly go, too. Any couple walking around with a pink-winged dog is probably losing their grip on social norms and protocols, but they are definitely not near the must-eat-brains-now stage.