Guy's face fell at the mention of the contamination; so Asch knew. Well, Guy had assumed that Asch knew, but to hear it confirmed...it explained a few things. His desperation, why he was always in such a hurry.
Why he seemed to hate Luke so much.
"Something else, I think. Luke said you made him go on ahead and stayed in a room to take on some soldiers. They probably ended up killing you." Guy hesitated for a second before reaching over to touch Asch's shoulder lightly. "...Asch-"