How can I add a secondary reviewer to the reviews?
You can add a second reviewer to the reviews and they can comment on the review and share their thoughts. To add the second reviewer, find the review cycle you specified by going to the Reviews module and open the review of the person you want to invite a second reviewer to.
Scroll down the review page and find the review results section.
Here you can see the "Invite others for comments "button. By clicking this button, you can include the users you have determined as reviewers in this review.