STORIES IN THE BRAIN MATTER MORE THAN TRUTH IN REALITY
As this "story" does the rounds inspiring condemnation (quite rightly), the violent disgust and sense of new depths plumbed by far right fascists exist as a reality to fear in thousands of left-wing brains.
If it turns out to be misrepresented or even made-up, the specifics fall off the map but the sense of justifiable fear remains, focused on the right-wing. The time spent in the story where this violent mob did the crime defines how one feels more than ultimately finding out the source of that feeling was false.
This brain foible is exploited by all propaganda. It's why plausible lies prosper and aren't outmatched by eventual exposure. The stories give up their momentum hard. What chance does truth have when faced with the unthinking preference for simpatico stories.