"And just why do you think that the aforementioned investigation will never take place?"

Experience. They hardly ever do. And Troll, from what you say, you don't expect to see one take place either.

Why does it need to be independent? Because there are always people who want to cover up their mistakes, and maybe worse than mistakes. (cf The Widgery report on Bloody Sunday - even a formally independent report can be twisted, so long as the people who have the responsibility of reporting are susceptible to political pressure.)

Why does such an inquiry need to be open? Because the same kind of thing could happen in all kinds of places around the world, and finding out what went wrong isn't just a matter for the Russians to mull over in secret. People with the responsibility for preventing this kind of disaster need to have that information, the same way the doctors needed the information. And they won't get it, or not until too late.

Oh, there'll be a secret inquiry all right, and it might be quite searching. And there'll be a public report which will make sure that all the blame falls in a safe place. And the doctors who spoke up will probably find their careers shipwrecked.