I know who SHOULDN'T have died... Carla! She was the best part of the game.
Did Carla die though? or was it Ada that died? who's to say Ada drugged Carla swapped places with her, reprogrammed her memory to make Carla think shes Ada then through doing that Ada can be closer to her enemy (Simmons) without suspicion so she can get at him up close .......... nah just joking lol.