They're suing OpenAI
The (latest) news story: https://www.cbc.ca/news/canada/british-columbia/tumbler-ridge-shooting-open-ai-lawsuits-9.7328382
This will be a difficult lawsuit, as one side is bound to be "you should have" and the defence will be "there is no law that requires".
It will also be an important lawsuit as it pits the need for morality in technology against the lack of regulation of new technologies (because it's hard to regulate what is yet to exist).
We all 'know' what the outcome should be, but that doesn't mean it will happen. The ruling inside the court of law is bound to be different from the ruling outside in the court of public opinion.
The important part is really the latter: the need to keep pressure on both companies and governments to not allow technology to run amok, to control our lives, to ruin our world merely because there is no pre-existing legislation to cover new developments.
The bottom line for this particular case is that no outcome will make up for the tragedy in any way, and it would be a further crime if whatever the outcome is it makes no difference in preventing any possible future tragedies.