It's quite clear that she is really the daughter of Sir Alan de Richmond, 3rd Constable of Richmond Castle, and his wife Olivia de Croft - unfortunately, due to previous misadventures in this area, BOTH sets of parents - the right ones *and* the wrong ones - have been Mastered.
(There's just no way she's a descendant of Losoard - so was Jollan de Neville II, and they would have had to get a Papal dispensation.)