The Island of Destiny

On the back side of this note you see a drawing of trees, mountains and a river. At the head of the river near the base of the mountains, you see an "X" marked on this drawing. It's a map! This must be where the temple is! Also on this map we see what appears to be a crudely drawn airplane and a giant monkey. You take a few moments to decide whether to go after Sabrina towards the river and temple or look for a way off of this island and look for the airplane.