After the cutscene, exit the room into the outside world, go to the bottom of the stairs and look right and proceed to the fence on the other side. When there, at the fence, look left, take your syringe, and stab the man ahead. If he is not there, just follow the path when you look left at the fence and you should see him. Drop all weapons, take his envelope and clothes and proceed to the gate. Wait at the door and allow the man to search you.
When done, look left go there and enter the door on the right. Now go forward into a big room. Go the double door in the upper right. Now go to the door on the left. Find the bartender and talk to him. When he gives you the invite, quickly rush back into the party room, now go to the buff white biker standing near a door. Let him search you, then enter the door. Don't wait for the bartender. Go to the stairs leading up. Enter the door, and if you did this fast, then if you look to your right, your target is there. Go behind him and fiber wire. Pick up the safe combo from his body and wait there. The bartender should come.
When he does, strangle him. Leave both bodies there and take the bartenders clothes. Now go to the target's room and find the safe. Take the photos. Now go back to where the buff biker is. This time, go down stairs and go to your 2nd target. Remember to walk when you are near bikers or your cover will be blown. Press the electric switch and exit the building from the way you came by walking. Now go to the gate booth which is where the guy who first searched you was and press the button. Exit the area by the gate, and go right to the fence. You are done.