After 2 years of Marriage, Must be Accompanied with Divorce Waiver

The problem here is that it seems that your friend never even received the conditional residency.
If your friend did receive the conditional residency, then a petition to remove that conditional residency must be filed before the termination of the conditional residency card.
If a divorce occurs, then it must be accompanied with the divorce waiver. It is possible to get the permanent residency under these situations if everything is properly done.