And if I opted to collaborate would this decision be partly driven by a desire to safe myself from potential Nazi ethnic cleansing? Or was it seen as an opportunity to project my own nationalist or racist tendencies (the Ustase or antisemitism in the pale of settlement for example)
You would likely be killed or otherwise mistreated on the basis of your being Slavic. If you chose to collaborate you might extend your chances at life but you’d still be mistreated by the SS. Probably used as cannon fodder or possibly just outright killed. There were Ukrainians who collaborated with the Germans but were still mistreated and killed because no matter how much they collaborated they were still Untermensch to the Nazis.