Help destroying BOS fallout new vegas?

Hello, i need help to destroy the brotherhood of steel in fallout new vegas quest for the NCR. i made the head paladin hardin the elder, but now I cant find the 3 card keys to destroy the base. I got the key from hardin (whenhe is the elder) and the scribe. Idk where the last one is. McNamara doesnt have it now cause he's just a knight now. is there a new pally or what? does ramos have it?