So now you have a measure of the maturity of your friends. The responsible and respected thing is to face up to one’s problems. Hoping things will blow over or go undiscovered is not a good approach in life. If you tell someone about your problem then 2 things can happen: (1) they appreciate your honesty and maturity (2) there may be a way to work things out if your employer/school/spouse finds out early on. If you try to duck then when the problem is discovered they will realize you knew about it all along and didn’t say anything, which isn’t going to buy you many points or leniency.
I’m not saying calling them now will change things, but its more likely than if you wait until they review your final transcripts. An approach I’ve seen recommended is to say essentially “I’m sorry, I accept responsibility, here’s why it won’t happen again”.