A student indicates she submitted a quiz. I see no attempts within the speed grader log.
The student's analytics also do not show any attempts for this specific quiz.
She sent me a web link that she received via email identifying her "score", but I am unable to access this link.
How can I know what attempts were made on a quiz aside from the speed grader log or through analytics?
Contact your school's Canvas admin, and ask them to investigate her page views. Provide them with the URL of the Quiz in question (should be something like https://schoolname.instructure.com/courses/26339/quizzes/15960 ) then ask them to look for the participation checkmark for that quiz. They'll likely need to know roughly when the student took the quiz (or at least a rough date range).
Not saying that's a guarantee, but it's a good way to check.
You can also check the quiz logs - https://community.canvaslms.com/docs/DOC-10090-4152295598
But if it's not in speedgrader or analytics or the quiz log, then there's a very good chance that the student's attempt was not captured, which should have happened the moment they started the quiz.
Click on the quiz and Moderate this Quiz. You should be able to see if she has attempts there. If everything auto-graded you would be able to see the grade in the gradebook. If she recieved something from her notification settings, then support would be able to tell you that as well.