Wait a minute so THERE IS NO REASON FOR HER TO PRETEND TO BE A MAN AT ALLL YAAAARGHHGHGH
The Emperor basically said that he's willing to forgive her father if she spends the rest of her life in servitude. She should have told him at some point arrrghhhhhhhh
EDIT: I am re-reading btw
EDIT2: And, well, I guess it's not something you can just come out and say