Thats an interesting post. In the UK certainly here in Scotland there are free "Biker Down Courses" run by the local Fire Stations.
The course lasting roughly 2hrs was excellent, classroom and practicaI...I attended one in 2018 and will do a refresher this year coming.. Sad to say I've forgotten a lot, however the things I do recall were vitally important and in no particular order. As it was being ran by guys who've attended these incidents their choice of words and language really ran it home to us all..these guys don't fuck about when dealing with a downed biker..
Traffic management at both ends assuming sufficient manpower should be appointed immediately.
As you say someone has to take overall control and direct everything.
If the rider isn't breathing he's dead, so helmet off is essential and its unlikely you'll make anything worse.
Same if the riders strung up in trees and not breathing get rider down as fast as possible..anyway you can.
If riders in a bad way, don't faff about trying to get leathers off properly, cut them open with a sharp blade.
We were also shown how to remove a lid properly BUT it involves leaving the person kneeling behind the downed rider and supporting the neck till the professionals arrive...so it's not wise to be the controller and THAT person unless everything is running smoothly at that point..
Who runs it? ... The courses are primarily Provided by Fire and Rescue Services across the UK and run by off duty Fire fighters. The majority of which are bikers volunteering to put something back into biking and hopefully helping to save a life.