I don't know what to think. In a way it's refreshing to know that someone in the Church would carry on with a woman pretending to be a man. In another aspect, it's disheartening to think they would want to carry on with the Pope if they thought that she was a he. There certainly does seem to be a bit of gender confusion-even back then.
But why the author felt the need to throw in this comment is strange:
It's important to remember that even if there had been a female impostor pope, this would just mean that an invalid election had taken place, nothing more.
Sounds like he has his doubts.