When Rives is attacked by the creature while in the van, he defends himself by stabbing the creature multiple times. Seconds later, the creature pushes the van down the hill, causing Rives to be thrown to the back, at which time you can see that his knife is still in the sheath on his belt.
Shadow of boom mic is visible on the hospital wall.
During the flashback to Orville's childhood encounter, a crew member's leg is visible on the left-hand side of the shot as the family exits the car.