Why do blinds work on Lee Sin?

Or why a pirate can kill death itself

wait so then how does the daredevil function?

{quoted}

Why can Lee Sin see what's happening in-game? He's blind, it doesn't make sense that he'd be able to see.

Now you're just being stupid. We all know that he can't see anything and the summoner controls him. In Lee Sin's own words: "Your will. My hands.". He can't see what's going on around him, but his summoner can.