Nope. Maxie's emipre was doomed no matter what. France had already removed its troops from Mexico do to the looming war with Prussia. And even without the war Napoleon III was begging to realize it was not worth it. Furthermore Max didn't really have suppourt of that many people he was way too liberal (probably more so than Juarez) so ended alienating the conservatives that originally brought him over. Ironically most of his suppourt came from Indian casiques like Mejia, that is people like Juarez; Indian governors and landlords whom the Spanish had respected their property and that had so far enjoyed special privilidges compared to the others of their caste. But since Juarez was one of them as well even their loyalty was split.
If the Americans don't suppourt Juarez it is likely the conservative gain power and establish a centralized republic jot much different from what Diaz did later on. Except the Church would enjoy more privileges.
The war of reform was much less about what type of government should Mexico have than about who should govern it the criollos or the mestizo.