What if Yugoslavia did not have its spring 1941 coup and this allows the country to "keep its head down" that year, remain a formal Axis member and trading partner of Germany that doesn't have to do much of anything in terms of a major contribution or DoWs (like Bulgaria in OTL)?
I think the lack of a Yugoslav campaign, the consequent occupation and partisan movement are simply not going to change the outcome of the war, and Nazi Germany and its allies, indeed all Europe, will end up split between areas conquered or liberated by the Soviets and areas conquered/liberated by the Anglo-Americans.
Which side will occupy/have the greatest influence/control over postwar Yugoslavia?
A) Soviets
B) Anglo-Americans