They don’t fuck around with aviation investigations.
Whoever did it better leave absolutely no evidence and melt the gun before the alphabet squad comes pounding the door in.
That or it’s just a lone wolf good ol boy who deeply regrets his medication made him do that, and his pain and suffering from guilt is punishment enough.
Having done exactly 0 research, I going to assume it’s one of those “DO NOT PRESS OKAY UNLESS YOU ARE EXPERIENCED AND KNOW WHAT YOU ARE DOING” and someone went “pffft I know what I’m doing. click now what does this option do…”