If you are looking for the "smoking gun" in the 90 photos, you will not find a weapon or a third party. What you will find is the visual diary of two people slowly realizing they are not getting out alive.
Panamanian authorities concluded the women likely got lost and succumbed to the elements or an accidental fall. Kris Kremers Lisanne Froon All 90 Photos
Here is an analysis of the timeline, the evidence, and the significance of those final images. The Context: A Hike Into the Unknown If you are looking for the "smoking gun"