Unlikely. JK Rowling has money. She is not desperate. She likely has a certain amount of control built into the contract. Very likely has certain things she can veto. To help you understand, during the 80s record companies had crazy control over the artists. This is why many bands sounded just like the next. How ever the gods of Rock like the Stones , ACDC, VanHalen and others still sounded like themselves. They had money and could tell the labels to f off. They could do what they wanted and still make music. JK Rowling is in the same situation.