While searching on Revisionist sites for any tiny straw to support a possible conspiracy for what they call the "hoax", I came across the blog posting Defence witness disappears from Belsen trial from
"Far more important than the absence of a witness is the fact that witnesses are not going to testify because they have been in conversation with witnesses for the Prosecution. If that be the case the Court will have to do something about it."
"From the evidence it appeared that the usual grounds for inferring people had been gassed was that they disappeared, but the same thing would have happened if they had been sent away to a factory or to another camp. With regard to Block 25, it might well have been that that block was used as a staging block for any party that was to leave the camp after a selection"
For the record, if sick or emaciated Jews were selected in Auschwitz and sent away, then certainly not "to a factory or another camp", but as useless eaters straight to the extermination sites.