Before I read this, I was assuming an actual threat, albeit a joking one, had been made. But based on this description, it’s not clear to me how the offending post could have been construed as a threat, rather than merely a bit of mockery and satire. If the poster had been both in earnest and praying for a violent act, I would understand why the service had an obligation to at least check it out. As it was, she was both joking, and joking about praying for something rather than about doing it, and joking about praying-rather-than-doing something she had no actual power to do anyway.
Scary stuff. I wonder if it doesn’t merit some hard-copy letter writing.
ETA: On the other hand, someone is claiming that this is a screen capture of the actual post, and if so, it’s less mild than the summary implies. I’d still maintain she’s not actually threatening to take any action or suggesting that anyone else do so, but if the screen capture is real, it’s a more subtle distinction than I was initially assuming.
ETA further: Here’s the Google cache of the relevant post. (Got down to the second 10/14 post.) So the screen shot is accurate.