Think you are going to have to take a deeper dive into the course.
Go go the course: USJ hors murs? and see what's in it. And is it guest only with no other roles that can sign up?
Login as Yammine Yammine. Go to this guest accessible course and see what user can do. As well as what module is ID 17416 (mouse over whatever to see what url)
What system wide or course roll does Yammine Yammine have?
What is 'Item with ID 17416' ... a glossary where participants in course can add entires? (that's a guess)