While she had a few seconds to spare before she was surrounded, she was really cutting it close by the time she had attacked, and when she did, she felt that maybe her assessment was maybe that she was even a few seconds too slow since when she moved towards the big dude the remaining people started running instead of the slow walk that they were doing to surround her.
It was too late for her, though, to make a change in her plan, and based on her initial impressions of how the scene was going, she felt that she had made the right call to attack the big dude since while she knew that he was significantly stronger than her, he appeared to be unfamiliar with what he should do and just swung the bat in an arc aiming right for her head.