KIA as in Killed in Action? If it is, could be talking about Lucky's alternate, not Lucky himself.
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Then again, Lucky's alternate is already dead as far as I remember in the story. If I'm not mistaken there's a reveal that Anton swapped his alternate with Lucky's, then when Velvet (or whatever his name was) died, Lucky lost his reflection 'cause he's dead but not exactly. Can't remember what was Anton's fate, something about "the Machine".
Maybe we have some really bad news heading our way, or a genius twist in the story.