On the way take out a dozen or so scattered Germans.

Return to your position and use the crater to hide and run towards the large metal gate to the north, where your teammates will blow it open with explosives. The remaining two bunkers are connected by trenches and are not difficult to find. The bunkers are narrow, so throw a grenade into the entrance at the back and then go in and sweep the area, taking all the bunkers and meeting up with your teammates.