After reading about Belle's latest shenanigans re: the baby gate, someone suggested that I turn the chairs around so that she could not climb them. This sounded like a good idea, so I turned them and then I bungeed them to the gate so that Belle could not move them. I then put the dogs out and went off to do reloading stuff prior to a range visit tomorrow.
Alas, the next time I checked, Murphy was again the solo dog on the deck. As for Belle...Yeah, she's on the outside again.