They were stuck between a rock and a hard place. Both Poland and Russia wanted the Ukraine. The Poles divvied up Czechoslovakia with the Nazis. The Russians gave the Nazis a free hand to invade the West via the Molotov-Ribbentrop Pact, and helped supply them in that effort. All the players in the war were despicable in some form or fashion. Bandera at least had the excuse that Ukraine was friendless and being attacked from all sides.
That's crap! The Nazis could care less what the Poles did, they knew their turn was coming...and the Cieszyn region was stolen from the Poles in 1920 by the Czechs, and since Czechoslovakia ceased to be a country in 1938, the Poles then moved in.....There was NO collaboration between the Poles and Nazis in this matter.