Mithias heard it, and Magnus probably did to. Did Martin really need a distraction that badly? ...probably yes, but if Magnus opened fire, he would reveal his location. Certainly one of them was dead meat. The helicopter had landed and the small SOLDIER team would be joining the fight. Mithias was still waiting on Miller to give him more information. 

Survival for Martin or Magnus looked fairly grim. The ancient vampire was right. They shouldn't be here.