This article explains how to add an external user to your Prime Account. An external user is someone who does not belong to the immediate organization, but to perhaps a partner or an associate concern. Adding an external user allows them to participate in training you enroll them in and take on any role you may give them within the LMS.
When a learner fails to meet deadlines of courses they are enrolled in, their manager and skip manager can be notified. This Knowledge Base article shows you how to trigger these notifications.