we currently have set up one course with several assignments. However, one (and only one) of these assignments should be graded by an external teacher. As a consequence, only this assignment should be visible to this external teacher.
On top of that, as the exercise is confidential, we have to make sure that no-one aside this external teacher is able to review the assignments.
For the time being, I have the external teacher as Guest of the course and non-editing teacher on that particular assignment.
Is it enough to guarantee confidentiality?
Is there a way to force the 'revocation' of rights on the assignment from other people (the equivalent of a ‘deny right’ on NTFS / Novell)?
Thanks in advance for your help.