Dustin just waves Ash's explanation off at this point. No use trying to assign blame anywhere (especially not when it's so much easier for Dustin to just blame himself and get on with his life), corroborating data points involving robots or otherwise. It's when Ash gives him a number that Dustin actually perks up - and looks properly annoyed.

"Yeah, yeah, I'm not gonna die," he says first at Pikachu's fussing, before narrowing his attention in on Ash. "--Is that an estimate, or have you actually measured his output before?"