Coincidentally, the latest episode of Darknet Diaries tells the story of a similar victim.[0] Again, the goal was to capture their Instagram username. Similar antics employed. Fortunately, it doesn’t end in tragedy.
I came looking to see if anyone had posted this. The thing that got to me about that episode was the complete lack of empathy (mild spoiler, I suppose) shown at the end, which is probably also more than evident in the OP's tragic conclusion.