There were very few gay inmates in Auschwitz and it is possible that there were none left there when the camp was liberated. As far as I am aware there are no reports of the Soviets finding prisoners with the pink triangle (every prisoner had a mark on the clothes identifying his or her category).

First of all, homosexuals were only persecuted if they were German, as homosexuality was against the law in Germany. Most homosexuals who were sentenced were sent to ordinary prisons within Germany, a minority were sent to concentration camps within Germany and only a tiny number were sent to Auschwitz, which was in Poland. These were mainly Volksdeutsche (ethnic Germans) living in Poland. It is estimated that less than one hundred homosexual men were incarcerated in Auschwitz. At least half of them died there.

In the face of the advancing Red Army, the SS evacuated Auschwitz in January of 1945, taking tens of thousands of prisoners on death marches into Germany. Only 7,500 very sick inmates were left behind to be liberated by the Soviets. If by any chance there were one or two of the 100 gay prisoners among these, it would have been easy for them to simply remove the pink triangle from their camp uniform and blend in with the rest.