Forum:Plz help me unglitch super marcus sweep

hey guys i stupidly glitched super marcus sweep mission on the knoxx dlc and now im down as i can neverenter the armory again ever!!! the only wayto fix this is to join someone elses game who hasnt glitched it wrongly!! if anyone is on this mission then plz allow me join i need to be able to complete this i want to see the armory again plzzzzzzzzzzzzz!!! msg me on here as my live is not on at the mo but i can get it on as soon asi need to and if its for the armory again hell as soon as i know someone will do it ill get it then!! thanx :)