No, you do not understand systematics. Your comparisons of Maxson and Wilson's study with that of Moriarty and Cannatella's are flawed. They are not addressing the same question; the later study is only looking at a single clade within Maxson and Wilson's. For what Moriarty and Cannatella attempt to do (address relationships within Pseudacris), there outgroups are fine. They're not attempting to resolve relationships among all Hyla. And the polytomy in the MP tree does not contractict the topology of the ML tree.