A state engaging in an official process of finding the facts is called litigation. What should be sufficient showing to trigger this litigation against a prosecutor? In this case, it was a journalist writing an article. So you're basically saying prosecutors should be subject to litigation based on articles by journalist.
The state has already satisfied itself sufficiently to reverse a murder conviction. If the investigation that led to that course of action was causally descended from an article written by a journalist - what of it?
If you believe that the actions taken by the state up to this point were unwarranted, say so explicitly. Otherwise, please recognize that I am not talking about journalists here.