the only thing Labradors hunt are scraps

As Flatfoot says ... most dog handlers are there because they want to be and thier 'crew mates' are just that, we dont know the full circs but it takes less than 10 minutes for a dog to cook in a car and however quick you think you are going to be its never quick enough to leave a dog in the car.
Most of our dog vans do have aircon but they are unreliable and (I think) need the engine on to work.
Most of ours van share so its quite normal for them to go to work in private cars before switching to the van
None the less a very sad story.