Rag,
It is totally inconceivable that the police could raid any office in any major enterprise and the subject of that raid be able to keep it a secret from their superiors.

It is illegal for the police to divulge any information found in a search if it does not relate to a crime.

The searches of Green's home and offices revealed no evidence of any crime and should never have been conducted.

The leaks themselves were judged by the CPS to be not secret and not a threat to national security. The DPP at that time was Keir Starmer, now a Labour Shadow Minister.