Well her fire team were all part of "The Hidden," right? Or I assume so, since she was part of that organization. Being a sort of mix between secret agents and commandos I'm sure they could be trusted with her secret since they're being trusted with all of the intelligence information from the Tower. Again, the theory has it holes, I just love the idea of her being Taox because of her deep seeded hatred of Oryx and her bizarre psychic connection with him.