The subject of "Dachau gas chambers" is controversial, with some saying they were never used for their intended purpose -- murder.
What's known is that hundreds of clergy were sent from Dauchau to the Hartheim Euthanasia Centre.
Curiously, I can't find the name of Father Cziempiel among the famous victims of either Dachau or Hartheim Castle.
Dachau gas chamber building:
Hartheim Euthanasia Centre:
Drop the ‘i’ from his last name.
Wikipedia shows him as having died in Mauthausen, which would make some sense. The site that Homer is using is not known for its historical rigor. It’s pretty bad when folks will trust Wikipedia over a site that should know what it is doing.
It’s clear that many of the Polish priests went through Dachau; its also clear that they were taken elsewhere for execution.