Well, after much experimentation (and abandoning the inaccurate instructions) I got the dog spy camera up and running.
I regret to say that of 40 photos, only three were not of the darkness between the dog's chest hair and his pillow. Also, the dog camera doesn't work too well at night with low light.
I imagined this graininess to be Gary's chair:
... and I felt certain this was the food in the bedroom:
But it took me five minutes to determine what this was:
I thought the dog has climbed into the attic when my back was turned, then I realized it's the dog's eye view of the closet when I'm on the step ladder (the white frame.) the circular eye shape in the back is the truck jack I use to jack up heavy things.
I think I need to keep tweaking the body position -- maybe hanging from the side of his head, not the front. And of course, no more night vision photos.