It is possible that students may not be able to see their submission views for a quiz after the end date has passed. The quiz with the indicated end date and time does not show up in the list in the Quizzing tool.
This is a known issue.
Ask for assistance if this problem occurs on your campus. If you are at UW-Madison, please contact the DoIT Help Desk. Otherwise, contact your campus help desk.
For Site Administrators Only
The problem may be fixed by enabling the permission "Allows out of date quizzes to be viewed in the User Quiz List" under "Quizzing" at the "Course Offering" level for the Student role in "Roles and Permissions".