Again, sort of, but not quite. The documentation on concern for soldier's welfare when faced with mass murder was not from the camps (and it's also worth noting that the camps were quite diverse- from work, punishment, containment, relocation, prisoner d war, reeducation, death etc. Of course the outcome was overwhelmingly death, but that wasn't the intention of a number of the camps, though they changed over time) it was from the Eastern front and those working with the death's head units: it was complaints from the einsatzgruppen that precipitated the development of new methods of mass murder. Similarly the idea of gassing people was initially used as part of the euthanasia programme against genetic undesirables: then, in response to einsatzgruppen complaints they developed mobile gas trucks aimed to alleviate the stress in those divisions. The first static gas chambers (and the explicit development of a final solution after the wannsee conference) weren't opened until 1942- and, chillingly, it was a financial decision, not an ideological or pastoral one. It was considered to be cheapest and most efficient to ship Jews to static sites to be gassed- and so the death camps were born