It's as ridiculous as it sounds, but they go through a lot of effort on the corporate side to make sure they're in the clear. It's a lot of CYA paperwork and stuff demonstrating they've done what they could have. And then out-of-court civil suit settlements that are sealed so no one knows the details and can't form class action suits or coordinate well enough to initiate a criminal investigation (their family member's accident seems like a one-off to them, they don't know the extent of the problems).