I am attempting to use the Canvas API to retrieve the quiz answers for all past submissions for all my students, in order to analyze their earlier responses. I am able to retrieve past quiz submissions for quizzes using the 'quiz/:quiz_id/submissions' endpoint, which gives me quiz_submission_ids, which I can then follow-up on with 'quiz_submissions/:quiz_submission_id/questions'. However, it appears that I'm unable to retrieve all of the students' answers from these results. Depending on the submission type, it doesn't appear that the "answer" field is always populated. In particular, the 'fill_in_multiple_blanks_question' type does not have results. According to this appendix, I would expect this field to be present as a hash of strings to strings, and yet the field is undefined.
Am I accessing this field incorrectly? Or is there some other way I can get access to the entire previous student submission? Ultimately, my goal is to analyze every answer from every past submission for every student in every quiz, so a way to just get the bulk data would be a suitable answer too.