Prevent manager from assigning course to contractor direct reports

Summary:

Business requirement to ensure that contractors are not assigned training by manager.

Content (please ensure you mask any confidential information):

We are wanting to have contractors be able to take specific safety trainings but not any other trainings. In reviewing all the setups, i know that the global access groups will allow us to prevent them from seeing courses we don't want them to see in the catalog. But from what I am reading, that will not prevent a manager who does have access to the training, or someone with the learning specialist role, from assigning a course from the catalog to someone who does not have access in the global access group.