[Rokke]

The whole video shows the tractor pulling up to the scene. Obviously the engine is running fine. Without seeing the whole video, it is impossible to make an accurate assessment of the situation.

[Blood of Tyrants]

I suppose that the military's infrared capabilities could be sensitive enough to pick out the body heat of a human and ignore anything outside that range. After all, infrared frequncy is directly proportional to the heat of the object. All that would be required is to build a good enough filter.