One last time & I'll do it slowly with small words.
WE DO NOT KNOW THE ROE.
Based on the above statement, we can conclusively state:
WE DO NOT HAVE ALL THE ANSWERS.
You can bitch & moan all you want about the non-cooperating US government & cry "cover up" all you want, ROE will not be released to someone who does not have a need to know. I'm sorry to say, a British Coroner, no matter how ancient his post may be, does not have any right whatsoever to classified ROE. It's called Operational Security, or OPSEC. It will not be divulged. To do so would be reckless & negligent.
Now, you may argue to your heart's content about whether or not it should be divulged, but accept it as fact that it will not be. Therefore, you cannot know all the answers. That said, you cannot come to anything other than a guessed conclusion.
This "duty of care" nonsense you've picked up from your association with the EU is a slippery slope of blame & liability control - nothing good will come of it. It serves only the ambulance chasers.
It appears you either will not listen to reason, are intent on continuing to confuse politics with logic, and will cut your own throats to spite a despised PM. I think it's best if I leave this thread.