If you are not reducing your ethanol volume before winterizing, and are extracting at -65, I suspect your (current) winterization process is completely irrelevant.
The DE might be relevant, but logically, if the fats/waxes are going to precipitate at X temp in Y volume of ethanol, there is no way they are going to make it INTO solution under those (very same) conditions. If you want precipitation, you either get it colder, or use less liquor. Or both.