Currently, when you mark attendance for an ILC, the attendance page does not give you insight into the status of required uploads (or evaluations). Checking "Completed" will not update the course (unless the requirements are fulfilled), but the system will allow you to check the box and save the page without alerting you that the course isn't really being marked complete.
Ideally, you'd be able to see the status of uploads on the Mark Attendance page and the system would prevent you from selecting complete if the upload wasn't present. Alternatively, the system could just provide messaging when you hit Save.