IRB approval does not protect you from unethical research projects

I was shocked to read this article about a study of premature infants at the University of Alabama-Birmingham.  The study examined outcomes such as blindness in premature infants who were provided with varying levels of oxygen.  This 5-year project found that infants who received higher levels of oxygen were more likely to become blind, while those receiving lower levels were more likely to die.  The reason that DHS is now crying foul is that the researchers provided parents with a consent form that failed to adequately inform them of the foreseeable risks of participating in the study.  My question here is why the researchers, and not the university's IRB, are taking the blame for this.  Isn't the point of an IRB committee to ensure that risks to subjects are properly explained?  Why call out the PI by name and tarnish the name of a researcher who appeared to do everything that was required? Every university and health facility where I have worked requires that consent forms are reviewed and approved yearly by an IRB board. In this particular study, 23 additional separate IRB boards and a Data Safety Monitoring Committee reviewed and used the same consent forms.  If these researchers had the necessary approvals and believed their study had been judged to be ethically appropriate, why not lay the blame on an IRB that appears to have dropped the ball?  Instead of being addressed to one researcher in particular, I think the more appropriate course of action would have been to address it to the head of the IRB and members of the review board.