I think that if one's concerns are of a safety nature (e.g rocket blowing up and killing people) then one would be looking for a more guaranteed information source than the company's servers.
I'd be retaining my own lawyer and lodging printed letters, emails and data with them as well as keeping contemporaneous notes. It's a "proper" place, so you can't be completely accused of mishandling company information. And your lawyer can attest to dates, content, etc.
Doing that before seeking how the company responds to the bad news you're able to raise with them means that you already have your evidence stashed.
Expensive, but remember that a result of a fatal accident inquiry is that one might get a charge of negligence pinned against one, and being able to make that go away quickly and easily is an imperative; you need another job, fast!
That's not something that one wants to entrust to a discovery process involving data that management may be trying to track down and destroy... No data looks bad, but it is also their word vs yours, and there’s more of them.
There's engineers in VW who probably wish they'd done this...