I've run into alot of people like this one too. Either calling you a cheater or "you lucked out I am really much better then you are".
I think you did the right thing by not accepting the appology, but the wrong thing by asking him to appologise in public. Accepting the appology does nothing except tell the guy he can do whatever he likes in private and not worry about it.
He ones again proved his true nature by how pissed off he got after you said you didn't accept it.
Player: I do not appreciate you and your MASTER DEGREE words. Player: u are truly a jerk... most of the guys sincerely dislike ur atti Player: like a child does in grade school. You have alot of growing up Player: to do delirium..regardless of ur age!
I would've just let him keep talking then reported him using the ingame report + taken screenshots for extra backup.