While Bandera reportedly did work some with the Nazi government, he also spent years in a Nazi concentration camp. It is easy to forget today that many people who were against the Nazi ideology also had to deal with the reality of the situation at the time. The entire government of France and some of its people would be one example, the governments of Belgium and Denmark another. Many citizens of Denmark joined causes supportive of the Nazis, and some fought in SS units.
Bandera was primarily an advocate for Ukrainian freedom and independence, and his relationship with the Nazis grew out of his work trying to free Ukraine from Stalin. The Russian communists hated him, and he was murdered by the KGB in 1959.
Typical revisionist history.