With all due respect, the Marine Corps Balls are held all over the country at a time that is near to the November 10th Marine Corps birthday, but on weekend dates at locations convenient to the bases. So it is quite likely that the 18th is correct.
If they were I never heard of any. November 10th, falling any day of the week has always been my experience.......... Even former Marines celebrate November 10 in parties all over the Nation. I once attended a Birthday Ball party that included in it’s attendees former Marine LT and former California Senator and Governor Pete Wilson. It was a Tuesday if I remember correctly.......