At first thought I was thinking you should used dried material but then I thought.... you will be soaking/simmering the dried material in water anyways so what does it matter? Then I thought maybe the material needs to dry before the THC becomes psychoactive. Then I thought what if the baking process dries and decarboxylate the THC and makes it psychoactive?
To be honest man I don't really know for sure. You can make butter but how good it will turn out no clue. If you do use fresh frozen report back and let us know.