https://www.bbc.co.uk/news/uk-65687697
Dr Butler spoke at EPATH conference and questioned Dr Cass' actions and integrity.
'In the recording, which was then handed to Newsnight, he was also heard questioning the personal integrity of Dr Cass. He implied there had been, what he referred to as, nepotism around the choice of two hospitals in the south of England as the sites for new clinics - suggesting Dr Cass's previous involvement in them both had been a factor.'
Decent article from a Newsnight investigation, also includes comment from a detransitioner.