Here you go:
From Napoleon the Great by Andrew Roberts, pages 333-334:
'Wright next landed General Charles Pichegru, the former Brienne instructor, French Revolutionary War hero, and Jacobin-turned-royalist, along with seven co-conspirators at Bivelle on January 16, 1804, and returned to Walmer Castle in Kent, where British naval intelligence was based. Wright was acting under the orders of Admiral Lord Keith, commander-in-chief of the North Sea Fleet, who reported to Admiral Early St Vincent, the First Sea Lord. St Vincent's own orders from Lord Hawkesbury were that it was 'of the utmost importance that Captain Wright should be involved in the fullest latitude.' Other documents, including one from Keith specifying that Wright 'is employed on a secret and delicate service', connect the British government intimately with the Cadoudal conspiracy, at the highest levels of both. Further evidence of direct British government involvement in the 1804 plot to murder Napoleon lies in several letters, the first written on June 22, 1803, from a Mr Walter Spencer to Lord Castlereagh, a senior British cabinet minister, asking for the repayment of L150 for himself and L1,000 for Michelle de Bonneuil, a royalist plotter with several identities who is known to have met Louis XVIII's brother the Comte d'Artois (the future King Charles X) in Edinburgh during the Amiens peace. Spencer said the money had been advanced 'relative to a political intrigue planned by Lord Castlereagh to abduct Bonaparte in 1803', which was co-ordinated by Mr Liston, the British envoy to The Hague. (Plots to 'abduct' Napoleon at this time were transparent covers for his assassination.) Although there is nothing directly incriminating from the government side in the exchange-as might be expected-George Holford, a member of parliament who was Castlereagh's closest friend in politics, wrote to Spencer saying that if he would 'take the trouble of calling in Downing Street his Lordship will see him upon it.' This would hardly have been the case if Spencer had been a crank.'
It should also be known and understood that Pitt while out of office was 'in residence' at Walmer Castle in Kent as Lord Warden of the Cinque Ports and undoubtedly knew what operations were being conducted from there, unless he was both deaf and dumb or just plain stupid.
Again, if you have or have read the books, check the notes and bibliographies of the books and find the primary source material used to provide the information. Your characterization of Cronin's work is both wrong and unworthy of being said.