Damage on throwable item

I am trying to make a damage type that inflicts instant death to the player on activation where if the player throws an ender pearl and within two blocks it lands. I have a block that is

if -2 < (z delta movement of (entity/player))+(x delta movement of (entity/player)) and 2 > (z delta movement of (entity/player))+(x delta movement of (entity/player)), how can I add the  Throwable projectile of type (ender pearl) of shooter (entity/player) block on and inflict the certain damage and kill player if both are true?