Hi, here is my Walkthrough for this Mission. The Videos is
incl. Collectibles (XOF / Tapes), Rescue Achievement and i earn an S-Rang.The Mission is on normal not really hard. You have to extract 2 Prisoners (Chico & Paz) To clear this Mission is the Rating total matter, you can detected, you can kill the Enemies and reload the Checkpoint as often as you like. Take your Time and you have really no Problem to beat this Mission.
My personal finish Stats was Time: 20:12:09 and my Points was 69190.
regards