The data certainly looks to be in that API, but it's ordered reverse chronology, and includes all activity, course and non-course. There also doesn't seem to be a way to filter for a course or date range. I'd have to start making calls, going back in time until I hit the course I was interested in.
It seems to me Canvas would have a better way to call this data to assemble the Student Access Report.
Additionally, there's not a flag that indicates if an item is a 'participation' or not, but it would be easy enough to use my own logic for that. All Submissions, DiscussionTopics are 'partitipation', other activity is passive, not 'participation'.
Thanks, Glen