There was a good comprehensive post on the old Reddit Holocaust sub that went into great details about everything, but especially the bodies. It was just physically impossible to burn the amount of bodies in the given time, even spreading it out over the entire war, double bodies on the elevators, double in the ovens, with half the burning time it would be impossible. So of course they moved the goalposts and said it happened in East Germany, where the Russians destroyed all the camps and withheld I formation. As far as the graves none have been stumbled on but I do know of at least two "graves" that had debris and tons of concrete poured on top of them, I think it was also made a major crime to attempt to see what's under them.
"people"
Check out Dutchsinse on youtube, really good at this stuff and occsisonly goes into directed energy weapons and weird shit on sattelite imagery. Sadly he's not as active as he once was.