However, "fault" is in the deviation from a perfect world that caused the result. The author, showing concern and asking about the well-being of another person, is not at fault for the abuse he received. The police officer, abusing his position, is at fault.
To apply these to your example of your stolen laptop, I would say that it was partially caused by you, but was not your fault.
The way that I read Gorbzel's comment as that both cause and fault were on the author, not just cause.
Gorbzel's comment is pretty blunt: for sake of argument, it basically amounts to "[Victim] is an idiot and should have known better, for his own sake". But to me it is very clearly an assignment of "cause" not "fault" in your terminology.
I understand this from phrases such as "for […] his own well-being" and "to his own detriment", as well as the fact that it's phrased as "advice". These make clear that Gorbzel is saying that the victim erred from a self-interest point of view not a moral point of view.
If you read the comment with the preconception that every interaction has one side which is Right and one side which is Wrong, then you will see the cops portrayed as "Just". If you read the comment without that preconception, you will not.
I am very afraid of people with that preconception, because they pick sides and then try to stick to them by confirmation bias. Like the cops.
(Just in case it wasn't absolutely clear: my position is that the victim here was careless-in-a-way-that-would-have-no-negative-consequences-in-a-perfect-world, like I was careless the time I left my flat unlocked and a guy tried to steal my laptop. Whereas the cop's actions were criminal, like the guy who tried to steal it. Both sides are "at fault" in some sense, but hardly equally.)