Yes, I can see why you have a question. With those parents you should not get a white chick. That rooster is not a red sex link male, at least first generation. His parents may have both been red sex links.
Looking forward to the photo of that chick. I think it will have a white body and a red head when it feathers out.
@NatJ, that makes me think Birchen crossed with dominant white. Vero272, for that to happen that rooster could be the father but the mother would probably be black with a red or white head.