He could be forgiven, I guess in missing out the name of the camp. Auchwitz was liberated by the Russians in January of 45. When word first came out about the place, people thought it was just Russian exaggeration, until Black US units found Buchenwald in March.
But the liberators of the concentrations camps in the US area of operations (Buchenwald, Dachau, Therezienstat) were by weird fate either black or Japanese. And the uncle in question would have been white, and unlikely to have been part of those units.
US GIs who were Jewish were put into Buchenwald, so when the first troops found them, the reports were about abuse of US GIs. Dachau was liberated in April, (again by Black and Japanese troops) because US troops move south into Bavaria thinking Hitler had gone into hiding there. US troops US troops got as far east as Therezienstat, Czechoslovakia in May.
It just shows the usual 0bama lack of basic research or distaste for truth in any form.