On the "Evac" mission, I know that at the end, you're suppose to kill the boss of that level who is wielding the two swords. Then you killed the infected VC soldier, before climbing the ladder to the roof, where the Bell UH1-D helicopter is waiting to evac you.
Well, my problem is that the door at the top of the ladder is closed,after I kill the two that I mentioned, leaving me literally with NO escape!! Can anyone tell me what's going on here and if I can fix it?!?