To be fair, they could easily include new info in these documentaries. As you say, something about Murphy would be good. Though he didn't single headedly keep the flag flying during Munich, both Joe Armstrong (the chief scout) and Les Olive stepped up, as did the other surviving members of staff. Joe was my Grandfather and our family know his importance to the club in signing the players that Murphy and Whalley coached, but it's just not officially recognised (I'm working on that!). I passed a personal letter from Jimmy to Joe from April 1958 to Wayne Barton for his book about Jimmy. It's a personal letter, Matt, Jimmy and Joe were close. Jimmy referred to them as the "Three Muskateers".
"My Dear Joe, Do hope all is well with your good self and Sally. I wish to sincerely thank you Joe for all the grand work you have done for me. I really mean this, without you around I could not have carried on. As you know there are a hundred problems to sort out every day and you know the answer to most of them. Have Enclosed 2 15/~ tickets which no doubt you will be able to use.
I know it's hard Joe with things as they are at O.T, but do try and relax & don't worry about things. We have all had a very trying time, only a few of us will ever understand that.
Thanks again Joe
"Always your best friend"
Jimmy"
https://www.mirror.co.uk/sport/football/news/incredible-letter-emerges-manchester-united-12555474
So if Jimmy has been virtually ignored, Armstrong has been completely ignored. You can't argue with his record of discoveries/signings: Byrne, Charlton, Viollet, Stiles, Kidd etc... He was also the one that talked George Best into returning to Manchester.