The question is at what point is it considered "hacking"? There is evidence of corporate misdeeds on the company's computers. Under what circumstances can a journalist view it? At no point would the guilty company want them to for obvious reasons, but if the answer is thereby "never" that seems like a major flaw in the law. Whereas if it isn't never then when is it, and why?

Or to extend your analogy, where's the computer equivalent of an investigative reporter getting let inside under a pretense so they can snoop around wearing a guest badge instead prying open the back door with a crowbar?

The question at the trial will be whether a reasonable person would have believed the evil corporation authorized the requests. You seem set on replacing the evil corporation with society, interposing a sort of "it's a public good for this information to come out, and so we'd generally authorize it". But if the company itself clearly wouldn't have intended you to have that access, and you knew that, and you used the access anyways, then yes: you committed a crime.

Again: mere ToS violations are not enough to cross that line.