Visible crew/equipment: Just after Kevin is executed, you see the assassin walk off to screen left. However you see movement in the rear view mirror of the car on the far right hand side of the screen, evidently a crew member since everyone has been killed. (00:27:15)
Other mistake: When Jack sits down in room 2, his watch says 2:50, despite the time being 1:05. His watch is correct in other scenes so it's not that it's set wrong or broken. (00:05:00)
Answer: This is unintentional and a simple continuity mistake.
Ssiscool ★