from the
Orange County register:
View attachment 19691
it sounds like, essentially, the lantern will change colors or go completely dark when near trigger points. in rare cases, the lantern will cause something to happen in the park (there's a spider mentioned elsewhere). but there's really no indication this will work like the skeleton key, in that it is unlikely it will grant you access to special areas.
it sounds like the lanterns are sold with a map that shows all the interactive points in the park. so, that should pretty definitively answer this.