I don't know if heads should necessarily roll but this is going to be a huge PR loss for ND. We live in a blame-oriented culture in which people are routinely held accountable for things beyond their control. As Lenore Skenazy has said, we now live in a society that no longer believes in accidents. This is a good and a bad thing. But, in this case, the relevant decisions seem that they actually were very much in the hands of Kelly/ Swarbrick/some other guy and those decisions led directly to the death of this kid. It was an accident, for sure, but certainly someone was negligent. We'll find out, at some point, exactly who and how but neither Kelly and Swarbrick can come away with clean hands here.
I thought that myself when I read that article that talked about a Data Scientist(tm)