I feel reasonably comfortable sharing given I got my MD three years ago now: During my second year of medical school, we had quizzes about once a month on different aspects of the physical exam. They were completely inane, asking minutiae that I guarantee most attendings wouldn't have any clue about.
For those quizzes, I would get together with my friends (a good dozen of us), we would brainstorm the answers, and one person would bite the bullet and take it. He'd get his score, and the rest of us would then sequentially submit it with corrections. We'd take turns being the patsy.
I also know there were a number of other groups that did the same. I like to think that my participation in that activity has no bearing on my current ethics a half dozen years later.
Here's my point: none of us had any expectation of expulsion if we were caught collaborating on those quizzes. They're take home open book online quizzes for God's sake. I fully anticipate that if we had gotten caught, we'd have been in trouble. Perhaps a zero on all the quizzes. Maybe a nasty note in our files.
We knew it was wrong. But expecting expulsion? That's like expecting a thermonuclear response to a thrown rock. Or the death penalty for speeding. No way. I can't believe if the OP was in a similar situation but got caught that the first thing that comes to mind is expulsion. That's why I assume there must be something else.
