Sabotage?
**Sabotage?**
Possible. But its winter down there, and they flew into serious freezing rain. This guy covers a lot of plane crashes, gets right to the point, using his vast experience of flying a wide variety aircraft. He says that even with anti-icing equipment icing conditions can be so severe that it can overwhelm the de-icing boots, adding weight and destroying aerodynamics.
https://m.youtube.com/watch?v=ozinSmylTmQ