Forcefemming him wouldn't work to uncover anything.
She would be the worst fucking woman to have ever existed. She would literally still be one of the boys, never like other girls. She would be the pick-me-est motherfucker to ever pick-me, in such a way that she would be the one picking herself. She would treat you like an irredeemable misogynist because you dared to hope she would be less of an irredeemable misogynistic if she was feminized.

It might work for the sake of your perversions though. I hope you succeed in sneaking estrogen on her all-knowing godly blood.