I saw the video and it looks as though the dog could easily have been named "Fluffy" or "Buffy." If that dog was a threat, then I'm an astronaut.
It could easily be argued that the officers, in NOT closing the car doors, were spoiling for some action. This is an especially pungent emotion in the over-revved dull-witted LEO when confronted with a benign situation. Once they get that testosterone pumping at 2 gallons per minute, the LAST thing they want is to have it go to waste.
Reminds me of a boss I had on a job some 20 years ago. He pulled me into his office, ready to commit verbal gang rape on me for a full hour. Only problem was, I admitted my error and apologized within the first 5 seconds. This set him off even WORSE.
Michael