He gets it, of course. Knows what Mei has lost and knows she wants answer as badly as he does.

"I know you do."

But he'll blame himself--he always does, and part of his revenge quest is atoning for the many, many mistakes he made over the course of twenty years that cost them all so much.

"I'm gonna find the answer, but it's not a road I want the rest of you walking down."

Because he's already compromised so much of himself in the process, and he knows where this ends. It's not anything good.