Thanks for the suggestion. I don't think that would work, because there's no way to know if the student is viewing the quiz or taking it. We also wouldn't know when they finished.
I notice that the Quiz Submission API has a way to start and end a quiz. https://canvas.instructure.com/doc/api/quiz_submissions.html
Clearly, there's a status change going on there. I was just wondering how I could tap into it. Would I have to scan every quiz in the course individually to get that student's submissions and check their status? Or is there a faster way?
Also, as you pointed out, New Quizzes might be different. There might be no way to query their status.