> while in kanji it would have been "Muranara"

Not quite. If you change the order of some kanji, the general case is that the resulting text has no definite pronunciation. You definitely would not expect that the sounds assigned to the kanji in one ordering would be the same ones assigned in a new ordering.

This is a phenomenon the Japanese sometimes play with. In the novel Musashi, Musashi comes up with that name by reinterpreting the characters of his actual name (which, in the novel, is Takezō).