Other people will have to comment on the Anubis characteristics. Xolotl is not the nahualli of Quetzalcoatl, i.e. the animal double of Quetzalcoatl. He accompanied Quetzalcoatl in his descent to the undrworld to get the bones from which humanity was made in one of the creations. He is not really a "sacred" dog. Quetzalcoatl's twinness is represented by his being both the Morning and the Evening star through his association with Venus.
Question, I do not believe that the AE had worked out the Venus cycle so would t hey have known that Venus is both the Morning and the Evening star and is Anubis associated with both?
Bernard