OK, I have another confession about this one now. In doing research about Bar & Bat Mitzvahs and other Jewish traditions, and whatnot that I could use for these characters I stumbled upon the whole Bark Mitzvah thing and knew that I just had to use it for a super canine companion. As for making his "real name" be "Muzzle Tov" that actually came from looking up Jewish symbols online and coming upon an image of a Hanukkah card with a picture of a dog and those words on it!
As for the question of whether of not angels can speak the language of dogs, I guess that's just one of the eternal mysteries of the universe.