Are the scrutinies for the Elect only?

Yes. Because the prayer of exorcism in the three scrutinies for catechumens who have received the Church’s election properly belongs to the elect and uses numerous images referring to their approaching baptism, those scrutinies of the elect are not proper rituals for candidates. In their place the RCIA provides a Penitential Rite for those preparing for confirmation and eucharist and has kept the scrutinies and the Penitential Rite separate and distinct. There is no combined rite for these celebrations. (RCIA #463)