They've all been dealt with in countless books, but I'm partial to Carlo Mattogno, so I'm going to suggest you read the following books which deal with most of the witnesses in your list. Broadly speaking, the direct gas chamber witnesses can be grouped into three categories: (1) witnesses who claimed to have worked in the Sonderkommando and was interviewed by Soviet investigators on location at Auschwitz immediately after the war, (2) ditto, but interviewed by the British/Americans after they were evacuated from Auschwitz by the Germans (!), and (3) random crazy witnesses who came forward after the immediate postwar period and claimed to have witnessed gassings personally (incidental witnesses or as supposed Sonderkommando members).
What all of these witnesses have in common, categorically,
every single one of them, is that none of their stories are coherent or compatible with the orthodox reconstruction of gassings at Auschwitz. They
all tell either absurd, verifiable lies, or repeat common Soviet propaganda. Not a single eyewitness told a story that is in any way wholly logical, historically accurate or compatible with what modern mainstream historians say happened in the camp. It's easy to challenge Holocaust affirmationists to mention their favorite or most important witness, and then show them how these witnesses consistently told the most ridiculous lies. So for orthodox historians to use these witnesses, they cherry pick individual statements from some witness testimonies and then attempt to reconstruct a believable version of events, mostly ignoring the rank, role or status of these witnesses. That's obviously the very opposite of how the historical method is supposed to work.
As Callafangers has pointed out in many of his posts, one of the key strategies employed by exterminationists is to flood you with names, documents, quotes and dates, with the aim of overwhelming you with a supposed mountain of evidence, ignoring the fact that every single eyewitness has already been analyzed and debunked by revisionist scholars for decades.
https://holocausthandbooks.com/book/the ... witz-myth/
https://holocausthandbooks.com/book/son ... schwitz-i/
https://holocausthandbooks.com/book/son ... chwitz-ii/
https://holocausthandbooks.com/book/son ... hwitz-iii/