The other argument about taking the Zyklon out, and then, throwing it out, or putting it in water, there's no reason. The argument is nonsense.
Don't waste time running down any ridiculous false rabbit holes involving speculation over Zyklon being doused in water. IF this had happened it would have been told in eyewitness accounts. IF they doused the withdrawn Zyklon in a bucket of water they would have still had a lethal amount of diluted cyanide left. Remember we are talking several kilos of Zyklon in order to produce the quick-killing amount of gas claimed by exterminationists. Estimate this amount of cyanide water times the claimed gassing schedule at Auschwitz and you would have LARGE amounts of left over cyanide needing to be gotten rid of. If you put this down the drain fumes would probably result from drain pipes. But more relevant would be the large amounts of cyanide going to the camp's sewage treatment plant. Since Auschwitz lay in a swampy flat lands area that cyanide would have accumulated somewhere and have become a problem. If it flowed down the river it would have had recorded fish kills and poisonings.
It's silly to argue the crazy results of a false cover story that everyone knows never happened.