If there has been a fatal accident, there will be an investigation, which involves not moving things until everything is measured.
Launch drone, fly a couple of orbits around the scene and overhead, sweep up and continue operations. That will give enough information to completely contruct the scene in a computer and give much, much more investigation information that previously possible. Information in a format that can be shared with the defence under disclosure without prejudice.
I know the person that passed away personally, he was engineer in my team. I just hope that the yellow patrol driver gets done for life and that teach them a lesson.
BBC reporting that the unfortunate engineer had a heart attack, and the other driver a broken shoulder. No word if the attack was before or after the accident, but certainly reason to pause before condemning a possibly innocent driver.
Man dies in Heathrow Airport vehicle crash - BBC News
I am sorry for your loss, however and honestly point no fingers. Quite a few friends of mine have passed before their time, sometimes their "fault", sometimes not - but it is always painful.