WW2 Museum

[Khem Nefermed]

There were indeed camps where yehuborim were gathered, this wasn't an outlier as all nations at war had them.

Due to the country being at war (as well as direct attacks on key railroads delivering supplies to camps), there was rampant shortage of food and medicine, which led to some of the "bad living conditions".
Even still, there was definitely intent for the camps to be livable and humane, for reasons one can even google.

That being said, this debate about one moment in history is not worth getting in danger over.
There's more important, better ways to make a positive difference in others' lives without shoving this, admittedly, for most people these days, hard to believe fact down their faces.
It will only lead to trouble and repulsion.

Best case scenario, the other person already had that belief, in which case you achieved nothing as well.