"(Even in #1 the firing was not her fault - it was the manager's.)"
But in this case, it's not a simple binary case of was/was not "her fault". It's at least partly her fault, regardless of the accuracy of scenario #1 or #2. There is a chain of causality here, and it all starts with Adria's tweet/blog post.
I'd also argue that your two theories represent a false dichotomy, and sussing out your conclusion based on the idea that there really are only two possible explanations (throw in some personal anecdotes for good measure!) is, well... lazy.
Fault is a legal concept. There is always a chain of events with many events that were necessary. But who had the power to make the decision? Who made it? That is who is at fault. In this case that wasn't Adria. (Not that her behaviour is anything to be proud about.)
I'd also argue that your two theories represent a false dichotomy...
Actually they don't. Are we agreed that this event is insufficient cause for a firing? If so, then if this event was the real reason for the firing, then the manager fired for insufficient cause, which is my #1. If not, then there is more to the story, which is my #2. Those two possibilities are therefore logically complete.
However they are not mutually exclusive. There might have been more to the story, and yet the manager still fired for insufficient cause.
That said, what's going to happen now? The guy who got fired has just become a cause. If he's got any skills at all, he'll get another job. I'm confident of it.
Adria has become radioactive. She hasn't been fired, but if her employer keeps getting attacked because of outrage over this, that's a possibility. If she does get fired, she's going to be radioactive for a while. Her line of work requires her to be public about where she is. And no sane company wants to be included in the outrage aimed in her general direction.
But in this case, it's not a simple binary case of was/was not "her fault". It's at least partly her fault, regardless of the accuracy of scenario #1 or #2. There is a chain of causality here, and it all starts with Adria's tweet/blog post.
I'd also argue that your two theories represent a false dichotomy, and sussing out your conclusion based on the idea that there really are only two possible explanations (throw in some personal anecdotes for good measure!) is, well... lazy.