"full of narcos and rebel groups"
This area is 60km into Balamkú ecological reserve. Are you familiar with that area? This state (Campeche) if famous for being one of the safest areas in Mexico. No, there are no narcos or rebels in these jungles. You would have to travel several hundreds of kilometers north in order to find any danger related to narcos. Everything else you said is true: Thick jungle, hot and difficult to navigate, but humans are the least dangerous things in that area.