An accusation is false until proven to be true. It doesn't sit in a nebulous wonderland of "maybe." To expand on this, if I accuse you, right now, of sexually assaulting me, is it false?
It's false because it didn't happen, not simply because you can't prove it happened. Whether it happened or not is an objective fact, and the question of proof is only relevant to whether or not you can convince others that it happened. To flip your analogy around, imagine that you really are sexually assaulted, and the culprit is a smooth criminal who leaves no trace. The fact that you can't prove that he sexually assaulted you doesn't mean that it didn't happen, nor that you're lying when you then accuse him of sexually assaulting you. Likewise, if you then search around and discover proof, like a recording of the assault, that doesn't magically change your accusation from a lie to the truth. It was always true. You could make an argument for not accepting an accusation as true unless it's accompanied by reasonable evidence, of course, but that's not the same thing as automatically assuming that every unproven accusation is a lie and should be treated as such. In fact, we could turn your own logic on your statements about Quinn - you're accusing her of being a liar who drove an innocent man to his death, despite having no proof. Therefore, you must be lying.
It's doubtful she went out of her way hoping he'd kill himself (but it's not entirely out of the question, either). I'm not saying she was legally responsible for his death, but to say she isn't morally responsible for it (like Saddam was saying) is just outright wrong. If you attack someone's social status you can't act surprised if it's actually effective.
Is she morally responsible for his damaged social status and lost job, absolutely. No question. But morally responsible for the fact that he chose to respond to his situation by doing arguably the most drastic, permanent, and downright irrational thing he could have possibly done? Unless you disagree with that assessment of suicide, I don't see how you can blame a decidedly illogical event on someone via a logical cause-and-effect analysis.
They are. Businesses that are firing people merely for being accused of something are morally responsible for adding to a reprehensible state of affairs. They were more interested in covering their own ass financially and PR wise than bothering to find out what the truth was. But that's not terribly surprising, companies in general are immoral entities.
This wasn't a "company" in the sense that you're invoking, with a board of faceless douchebags in suits dismissing an anonymous peon casually and then moving on to the day's business. As the reddit post I linked to explains, Infinite Falls is a tiny dev with just a handful of people doing the work, and Holowka and two others being the main designers. Those two were the ones who made the decision to "fire" Holowka, explaining that although they had been friends and worked with him for years, they knew he had behavioral and relationship problems, and that others beyond Quinn had accused him of wrongdoing. I really don't see this small, intimate team promptly selling out a personal friend and key member of their team on the whim of a crazy lady on the Internet with seemingly nothing better to do than make wild accusations. And just looking at the financial/PR angle, showing any kind of solidarity or agreement with someone like Quinn would be every bit as controversial among the gaming community, if not more so, than standing by Holowka and risking an angry op-ed from
Kotaku or
Polygon.