After adding fuel to the ambulance, Doc puts the can down at the rear of the ambulance. When he drives away, the can is gone.
Doc uses a fuel can than sounds empty as he moves it around and touches it to the ambulance, but he holds it at the fuel cap long enough to make it look like there was fuel in the can.
The two Germans put on the uniforms that they removed from unconscious Saunders and Caje, but for the rest of the show, Saunders and Caje have uniforms on.
As Doc walks into the garage to get a vehicle, the camera's shadow is seen moving along the left side of the floor.