Bandera was in Berlin and Sachsenhausen imprisoned by the Germans from January 1942 to September 28, 1944. Yes, he was an execrable fascist and anti-semite. But collaboration in the Shoah from Sachsenhausen was hardly possible.

From Rossolinski's biography of Bandera:

"It is difficult to reconstruct the exact date from which Bandera was kept in Zellenbau. The divergent accounts suggest that he was moved from Berlin to Sachsenhausen several times. Stets’ko wrote in 1967 that Bandera came to Zellenbau in January 1942.[1383] In an interview in 1950, Bandera said that he was held in Berlin by the Gestapo until 1943 and was then moved to Zellenbau.[1384] In an interrogation in 1956 in Munich, he stated that he was relocated from Berlin to Sachsenhausen in the winter of 1942–1943.[1385] Bandera’s prisoner number 72192 was

assigned to him in October 1943. His prison card shows that he was released on 28 September

1944."