So you're saying you believe the statistics regarding the number of deaths?

Of course. You say that as if the stats are unreliable. As if the Allies didn't spend years investigating and running trials, and then historians another 70 years going over the records and evidence. As if there weren't tens of thousands of Nazi documents detailing their actions, thousands of eye-witness testimonies including those of camp guards and SS officers, mountains of physical evidence and demographic evidence that the Jewish population in occupied Europe fell by many millions.

Probably the least reliable number is the estimate of Soviet POW deaths, and that's probably an underestimate. Stalin made a big deal about hiding Soviet war dead so that the Allies wouldn't know just how badly the USSR had been affected and how many fighting-age men had died.

But whether it's 15 or 14 or 17 million, denying that there were many millions murdered in the camps is as asinine as denying that Americans own cars or that the French eat cheese.

Where are the 15 million bodies?

Buried or cremated, duh.