Because you made an educated guess. And when you do that, you've already assumed that you're at least more likely to be correct than not.

[She waves her hand, heat trails following it.]

But no, there's no point in dwelling on should haves and could haves. You did finally come forward. So what exactly are these people like? What are they capable of? And what is your best educated guess as to what they're most likely to do next.