The Red Order: First Days of Eurasia- A New Order Spinoff

This was less Denmark and more the USSR deciding that Germany didn't deserve Holstein.
Still a Holstein puppet would make more sense in this case, as otherwise Denmark would either have a very large German minority (Like 30-40% of the population large) or a lot of useless empty land they can't settle (In case of expulsion). It could even be justified as a dumping place where all the Germans in Denmark proper are being expelled to.