What Happened to Two Dutch Backpackers Who Disappeared in Panama?

Mobile phones that had been unlocked with the wrong passcode and numerous flash photos in the dark.

El Pianista Trail, Panama

Kris Kremers and Lisanne Froon were Dutch students that disappeared in Panama in 2014. Although remains have been found that identify both females, no cause of death can be found. 

In addition, police have no idea who the murderer was or even if there was one. The girls' belongings asked many questions, but not as many as the remains when they were found.

Why had one of the women decomposed naturally whilst the others had bleached bones which looked to have been dismantled?