I've created a 'Publish as LTI tool' in a certain course with 4 scorm activities. One 'LTI tool' is the entire course. Then I have 4 'LTI tools' that are made to enroll in a single scorm activity. All these have the Role as Teacher and Role as Student configured the same.
When enrolling someone on the entire course LTI, they get the role Student. When enrolling someone on a specific scorm activity, they will be enrolled without the Student role.