Firstly, it’s Khornate, with an ‘a’.
Secondly, the Blood Ravens are not Khornate. Having Blood in your name does not make you Khornate. The Blood Ravens are a Loyalist Chapter.
Thirdly, if the Chief Librarian of the Blood Ravens did fall to Khorne, he would quickly lose his favour with Khorne or lose the ability to use his powers, as Khorne does not allow for psykers.
BYE