Why does he think those clinicians started working at a gender clinic for the sake of infiltrating it? It's not unheard of that people start working within a certain field and then change their mind on a topic that is related to their field of work because of their experiences. From one of the recent Times articles about children being transed: https://archive.li/zlM7O
The [gender clinic] said it was “a welcoming place for people from all sections of the LGBT community”, adding that it had made exploration of sexuality a “more explicit” part of the assessment in response to staff concerns.
Nevertheless, the clinician said that her unease grew after meeting an adult woman whose transition to become a man involved having a double mastectomy. She had since changed her mind.