yes what u just described might not have been wall hacking. it might have been auto shoot, in which case the guy just has to walk around and his gun will shoot automaticly at the slightest whiff of the other team.
my guess is that there was a guy behind that door and his autoshoot combined with his wall hack must have made him throw the nade!
and thanks for sending me the demos in advance!!
have a nice day/night/evening/morning
EDIT:: excuse my bad spelling and typing