Are you new to english? Also, I don't think thats a mistake. They saw Johnson get pulled into that airvent and only his gun came out. So they really thought he was dead. During the game, when you get split up from the SWAT, you find Johnson somehow. But then he dies from... acculty, we never knew how he died. We just saw him on the floor dying, then died. And the SWAT probably asked that just to make sure
sorry if my english is bad.
anyway, Hen said he was just lazy to fix the sound. so yes it is a mistake.
the SWAT guys didn't saw him being killed or die. just missing. he's MIA not KIA. and because johnson is not with you, the SWAT guy is talking like you probably didn't saw him.
edit: I DESERVE EVERY $ I PAID FOR THIS GAME! and because it's free i get 0$. lucky me!