Sure I hear you. I agree that this distinction matters.
What annoys me is that revocation is even an option at all. I think this scenario is such an edge case that it really doesn't need an exception, and if supporting it means having the power to revoke a degree, then in my mind it's a lever for abuse and not something we'd want to normalize. It seems, to me at least, like a petty abuse of power that they shouldn't even have.
The conduct in question happened pre-degree even if the punishment was after. I think that is a pretty important distinction.
most contracts cover conduct during the contract even if it only comes to light after the end of the contract, so that wouldn't be so unusual.