Plot hole: How did the occupant of the room where the dry ice was placed only burn his index finger when he picked it up? His thumb, other fingers, and palm were all undamaged. Was he wearing special gloves that had only the index finger missing when he picked up the dry ice?
Plot hole: The bodies were pink because of exposure to the lower temperatures created by the dry ice venting into the room. None of the CSI team noticed a chill when they entered the room? None of them noticed the bodies were cold to the touch? No one noticed that the body or liver temperatures didn't match with the estimated time of death?