As Robby said, other than "I'll Make a Man Out of You" nobody really cares about the songs (they can play "Reflection" in the credits if they want) so it's better if they don't bother. But hearing Mushu being taken out . . . . Mushu is a big icon of Mulan other than, well, Mulan, and trading him for a freaking PHOENIX?
To backtrack: Mushu was one of the Fa family's spirit guardians, which if you paid attention they're all the twelve animals from the Chinese zodiac which includes, yes, a dragon. There is no phoenix in the zodiac. The only reason I can think of them using such a flashy animal as a phoenix is that phoenixes are often paired with dragons in art and iconography. A phoenix is not the kind of animal you can really . . . hide, when trying to sneak into an army.
https://en.wikipedia.org/wiki/Fenghuang