Apparently they knew of its existence but because of the confidentiality of some of the accusers the report wasn’t made public & the head honchos didn’t read it as it was recommended that he could still coach.
However as they’ve now read it & seen what he was accused of &, presumably, proved to have done it had raised as I said safeguarding issues & isn’t behaviour consistent with being the manager of the England women’s team.
As such they’re perfectly entitled to sack him now regardless of whether they carried out proper checks when he was appointed