Glide ratio only counts if there is air to glide on. If you are flying low you are going to land/crash on what is below you. If the engine coughs, you are going to land on the tree/rock/water that is below you.
If you make the positive guess that a crash didn't happen, he was reported to have several means of communications that hasn't been heard from. Even assuming rough terrain that block transmission and he is at this moment walking out . . . Pretty slim, huh?
As popular and rich as he may be, the plane might never be found. If he isn't found, then the conspiracy theorists are going to turn this into another Amelia Earhart. You did know that she survived, was captured by the Japanese and was the emperor's sweetheart and Tokyo Rose?
Oh snap! Carl already has that covered.