While pushing up the hill, you’ll encounter three MG nests positioned in high ground. Fight your way while sticking on the left side. Once you reached a small passage between two rocks and a fallen tree trunk, your wounded ally will be there. Make sure to set a smokescreen or at least take out the enemies in front of you. Pull the wounded soldier behind the rock to the right to complete the heroic action.
For this heroic action, this will trigger after placing the first thermite at the back of the tank. Before doing that, make sure you cleared the bunker to the rightmost side of the area. Wait for the tank to move near the bunker then sneak behind it to place the thermite. As soon as you place the thermite, turn around and lob grenades at the enemy soldiers that will appear from the hill behind the bunker. You have to kill them quickly so you can rescue the strangled ally inside the bunker.