the article seems to suggest it wasnt even shared publicly, so I suspect that they hadn’t even considered the possibility that anyone who might think of it as a threat might see it. Posting that on a public forum, I can see the reaction, and I can definitely see an argument that the joke was in bad taste, but to be perfectly honest, unless one of their friends thought the message was sincere and reported it (which the article doesnt mention and sounds dubious) a private message like that really shouldnt have been visible to the authorities in the first place.