@Katrina
Considering she said the air was " sticky" afterwards my theory is that she reacted to the eather in the air somehow.
She might be one of the few who are extra sensitive to it as it's strange how they haven't found the location even if its in the middle of town.
They have to had found it somehow originally and i dont think people go around scanning every street corner for itr as that would most likelly be ineffective.
So i dont think anybody actually choked her, more like an allergic reaction and that would make the only candidate for the voice god himself.
but again i'm just speculating here, feel free to drop a spoiler if anybody knows if im right or wrong.