Yes, at bare minimum I agree with you - I am bigender myself, by the way, though definitely a trans woman first - but overall when picturing the whole situation it really seems to me like she was partially in the closet, the fact that she was in the military and was raised in a weird christian cult makes that idea, at least to all the trans women I've personally told about this, even more clear and obvious.

Obviously there's no smoking gun, but I think there is more than enough reason to come to that conclusion on her. Some of the strong pushback here is probably because, even if she was just genderqueer or non-physically-transitioning bigender or whatever, it seems very clear to me that most of the people (not you) arguing strongly against this in this thread are never calling to call her a her or call her Lilly and are arguing this point as an excuse to continue using he/him and 'Aaron' exclusively. Whether they know that or not, as internalized transmisogyny is quite rampant.