Visible crew/equipment: When the woman is performing an autopsy on one of the dead "creatures" the lights supposedly flicker and turn off. There is a hand visible flicking the switches on the lamp to the right side of the screen. (00:45:40)
Visible crew/equipment: When they first go through the door to the labs from the Ark, you can see the camera's shadow moving in on the door as Portman walks through it. (00:15:45)
Answer: This is explained by the fact that it was likely hiding, waiting to see what the RRTS would do. After all, the human test subject still had its personality, as far as is known. It would've waited to discover their weaknesses, stalking them like a predatory animal stalks its prey.