Double-Secret Extermination?

According to Sir Frank Hinsley's 1981 book, "British Intelligence in the Second World War", by 1942 the British were able to crack the secret German code and one of the things that was intercepted was communications between concentration camp commandants (Rudolf Hoess at Auschwitz) and those at the headquarters of the German order police (http://www.whatreallyhappened.info/decrypts/ww2decrypts.html - yes, it's a revisionist site but they quote directly from Hinsley's book). This is critical in that amongst the daily pieces of information that the commandants revealed were the "daily prisoner returns" (sometimes referred to as the "vital statistics") and these included the categories of "deaths" and "causes of deaths"..................................................................................So, what did they reveal? According to Hinsley, the vast, VAST, percentage of deaths (at Auschwitz and the other camps) were caused by typhus and other natural causes (can you say incessant Allied bombing?). Yes, there were shootings and hangings that were also reported (and, yes, these acts are most assuredly war crimes) but nowhere in any of these top-secret communications was there a single, solitary, mention of gassings (never mind, flaming pits, air hammers, electric conveyor belts, etc.). Zero. Nada....So, unless somebody has something else.......