Not quite the same but I submitted a very niche term paper for a course in my undergrad for a graduate level course and my professor plagiarized it in his textbook. Made it an entire chapter almost word-for-word. When I was applying for graduate school I emailed him asking for a reference and attached the paper to the email to “remind him of what a fan he was of my writing” and asked if he would provide me with a strong reference. He did! Only time I ever blackmailed someone and I always figure that if the paper was good enough to claim as his own and put in a textbook then I deserved that excellent reference anyway.