In Metal Gear Solid 4 on big boss extreme if you do die and have alerts and use special items do you still get the big boss corpse camo

No. To get Big Boss FaceCamo, finish the game in 5 hours or less with no alerts, no kills, no recovery items used, and no special items used on the hardest difficulty setting. To get the Corpse Camo, finish the game with 51 continues on any difficulty setting.