However, Himmler noted that this was too stressful (emotionally) on his men. So he sought for a more "hands off" and efficient method. In Poland there were discussions about shutting people into barns and setting them on fire. I think that may be in the same link above but not sure. However, they thought it was too easy to get caught doing this.
So now we come to testimonies. Since you do not accept Hoess' testimony, here are others.
This man says people unfit for labor were put into a barn, called the "white house," and gas cans were thrown in through flaps. After, the people were taken, dead and half-alive, and cremated: https://forum.axishistory.com/viewtopic.php?t=54393
This fellow was at the site during the buildup of Birkenau, and saw the bodies being stacked (which happened when there became too many dead to hide from the inmates), and describes the selection process and what was known of the gas chambers. He also describes a variety of other torments and summary killings:
https://forum.axishistory.com/viewtopic.php?t=51879
This man actually witnessed the gas tins being thrown into the chambers through windows, which I assume correspond to the "flaps" in one of the previous accounts, and which aligns, as far as I can tell, with the other accounts: https://forum.axishistory.com/viewtopic.php?t=63077
Very well.
In the early stages, the killings of undesirables, Jewish or otherwise, were done by shootings: https://forum.axishistory.com/viewtopic.php?f=6&t=252303
However, Himmler noted that this was too stressful (emotionally) on his men. So he sought for a more "hands off" and efficient method. In Poland there were discussions about shutting people into barns and setting them on fire. I think that may be in the same link above but not sure. However, they thought it was too easy to get caught doing this.
So now we come to testimonies. Since you do not accept Hoess' testimony, here are others.
This man says people unfit for labor were put into a barn, called the "white house," and gas cans were thrown in through flaps. After, the people were taken, dead and half-alive, and cremated: https://forum.axishistory.com/viewtopic.php?t=54393
The nature of the crematorium was well-knowm in the camp: https://forum.axishistory.com/viewtopic.php?t=51877
This fellow was at the site during the buildup of Birkenau, and saw the bodies being stacked (which happened when there became too many dead to hide from the inmates), and describes the selection process and what was known of the gas chambers. He also describes a variety of other torments and summary killings: https://forum.axishistory.com/viewtopic.php?t=51879
This man actually witnessed the gas tins being thrown into the chambers through windows, which I assume correspond to the "flaps" in one of the previous accounts, and which aligns, as far as I can tell, with the other accounts: https://forum.axishistory.com/viewtopic.php?t=63077
Does this answer your question?