It was known.
It's a shame we live in such a vengeance culture what we really want is for it to be public.
People die weeky in most hospitals because doctors and nurses don't wash their hands.
Get over THERAC, is saved lives and the programmer helped with that.
From Reddit AMA -
"My teacher does know the name, but is bounded by the courts to not release it. He knows the programmer is living in guilt and did say that he has left programming as his career. Although, it was not entirely his fault, as my teacher explained, the necessary software development process for a machine like this was not there, and no checks were in place.
tl;dr Cannot be revealed, but wasn't entirely his fault."
Nobody says it was; such disasters are often multifactorial. But given to his position that person holds key knowledge and insights into what went wrong that no-one else has. Without access to that information, investigators can only hypothesize.
This is why things like whistleblower laws and indemnity insurance exist, to enable the full and unvarnished truth to come out. How are errors meant to be fixed correctly when you don’t have all the information as to the cause?
Compare how air crash investigations work. Or research into procedural improvements to hospital hygene. There are things far more important than just finding people to blame.
And hospitals and doctors alike do get sued for medical errors and negligence - especially lethal ones. "But I saved 99 other lives" is not really a good argument, it's not a game of points.