There might be an interior issue (staining?) that keeps the overall grade of the book at 9.0. Call for grader notes to be sure.
Nice books!
As far as I know, the standing policy at CGC is that the overall grade of a double or triple cover comic is the grade of the interior most cover. Mr. Borock? Care to chime in here?
The covers are grade independently of the rest of the book. Then they factor the interiors to come to a final grade. In most case, if the pages are decent, it will be the same grade as the highest grade cover. Otherwise, there's probably an issue with the interiors, whether it's the PQ or some other issue (tears, stains)