You will need play the following sections in one go and will be given a silenced weapon which you should make full use of along with the Bursters. You CAN restart from last checkpoint in the event you are spotted, it will not disable the trophy. Basically you need to make your way to the Satellite Uplink undetected all the way. Chapter 4 “Six Months On” – Jungle Valley, follow the instructions of your partner as he guides you through the section and you should have no problems getting through the section undetected.