I don’t watch Fox News 24 hours a day, but they usually rerun stories, and I’ve never seen it. Also, why didn’t anyone do a follow up? Talk to the concert venue and get their information. Why in heck was she yelling that they were all going to die, and they are surrounded (something like that)? Does the venue have the name of that woman?
It could be just random chance. You've got 20,000 people, there are various interactions between strangers, a few might lead to altercations and arguments, and one person might randomly say something like this in anger. Perhaps just coincidence. However, I do believe witness accounts that it actually happened. Sometimes spooky coincidences happen.