Ok, I've seen this video before. Are you looking at some vehicles at the very top of the video frame? I can't tell if those are moving or whether it's an illusion created by old vehicles behind trees that change because of the movement of the helicopter as it circles the scene. At the end, once the camera pulls back to a wide shot, the vehicles aren't moving. IDK.
In the foreground are the BCI crime scene investigators (NOT wearing hazmat suits). They're looking around the black shed-like building, which many of us speculated held one of the grow ops.
ETA: That's one of the better helo videos from very early after the murders, giving a good view of the 2 UHR crime scenes. Recall, after a while, LE stopped the news copters from flying over the scenes.