I had a similar experience in college 35 years ago. One of my many jobs was to act as a proctor for exams so the professors did not have to "waste their time" sitting in a classroom while students took tests. During one exam, I saw several students cheating, passing notes and looking on each others' tests. When they turned in their exam papers, I segregated the exams of the people who cheated, and reported them to the prof, who did nothing. The next time I proctored for that prof, when I saw people cheat I took their exam papers away, ripped them up and tossed them in the trash. The prof gave those students a make-up exam. This in spite of the fact that our college had a policy of expulsion for cheating.