I found a way to solve this but am not sure it will work in all cases. My situation involves students who have switched sections. (PowerSchool is our SIS.) In "people" I viewed the user details and saw that the student's previous (completed) enrollment wasn't active, but could be deleted. (Use caution!) I deleted the "previous" (completed) enrollment and the user no longer showed up in Quiz Moderator.
I was not worried to try it with this student as the student hadn't "really" ever been in the other section and done any work. I'm concerned about doing this for students who submitted assignments in a previous section and are now in a new sections. I think I'll back up their grades and try it anyway. The grades are all from a previous semester. I'm just not sure what data is tied to the previous (completed) enrollment. If anyone knows, please pass along that knowledge. Finally, by accessing sections, below your current students, you can view completed enrollments so you can delete them there.
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