Breakfast for you plus a guest for 3 days (assuming you had a second guest) is 6 breakfasts. The terms and conditions (https://www.marriott.com/loyalty/terms/default.mi) say that if the property doesn't offer that as a welcome amenity choice, it is supposed to pay you $50 in compensation. That seems like a fair amount of compensation in my opinion, and I would have no problem simply insisting that they honor the $50, although if they wanted to provide a reasonable number of points (5000+ instead, I would certainly accept that). Typically properties use a favorable "exchange rate" when they give points away (something in the neighborhood of 0.6 cents per point), so I don't mind taking the points in lieu of cash.

Sometimes the guarantee seems like too much of a "gotcha" like when an agent at a regular "Marriott" simply forgets to offer the $10 coupon. I have a hard time saying "aha, give me the $100" in those circumstances. But in your case, $50 might not even be enough to buy 3 breakfasts, so I would have asked for it.