The correct opinion is she wrote children's books and since you are not a child you don't pay any attention to her.
Thanks.
I'm not sure that the average person really knows or cares much about Rowling and the controversies around her opinions.
That said, you said these people were fans of Harry Potter, and it's been my impression that the Harry Potter fanbase mostly turned against her for that stuff. So if you want to play it safe, you should slag her off.
(Edited 10 seconds later.)