Waalaikumsalaam and Barakallah brother,
One thing we must remember is that Canada takes a very open definition of misrepresentation. It defines misrepresentation as direct (done by you) or indirect (done by someone whom you employed or hired or who was acting on your behalf) action or lack of action that induces fault in operation of IRPA and IRPR. This means if you did something or if you forgot to do something, the law takes it as a misrepresentation.
Now what remains is how much likely immigration people are to act on it. So first thing first, know that an omission of a fact especially asked DIRECTLY in the form, CAN BE VERY LIKELY PUNISHED BY IRCC with a misrep finding. Second, it is BEST and even VITAL to get a professional advice on these matters from a lawyer. That 400-500 dollars can buy you a real opinion and pitfall that likes of us can never provide. Especially when consequences are rather extreme -- 5 years ban with no right of appeal.
Now, I can give you what have been told to me in consultations with lawyers in my own immigration case and those with whom I was deeply involved. These are experiences but not really advice.
First thing as I said before is that adding more information during your PR might work out especially if it does not contradict with existing information. PR application are supposed to be more through. That being said, your highest degree can be a vital piece of information used to decide your SP. So if you did not report your highest degree, well, you are hiding a vital piece of information which might lead to incorrect decision there. So this is not a direct application of the principle that I was told but might work out. I have not faced this situation myself but a sort of related situation as I said before.
One more interesting thing is that the person you mentioned has a masters but also a qualification from Canada. I will try and see if that Canadian qualification is enough to gather points required. Also try to secure a VALID ELIGIBLE job offer (it is a bit more complex so ensure you know it properly). With those points you might just not need those points of masters degree. You may just mention it as an activity and a qualifcation with no equivalence done and be done with it. Other option is to try gather more points via french language skills.
You see. I am trying to avoid that path in which your masters is looked deeply. Its becoming a bit of danger. You want to report it but show it is not a part of your profile for which you want to be evaluated. That IMHO will be the best recourse. Ofcourse your lawyer may know better.
Will it work? I hope it does. Its a plan, do get it vetted by a lawyer. I am not sure if this is the answer you are looking for. However, since I have not directly faced this situation so I can only speculate and try to play safe.
@imransyed In you friend's case too I will strongly recommend if we can avoid him having to depend upon his MBA for points. The path is a bit dangerous. That being said as always, a professional's advice is much better and supersedes any of our discussion.
Jazakallah!