When Veronica brings Dante lunch she tells him she will see him after he closes. This is the scene just before Dante finds out the boss is in Vermont and that Dante has to close.
Maybe this was said to show what a wimp Dante was. She probably knew he would be there all day, because he didn't have the guts to leave if no one showed up to relieve him
Actually, if you listen to the tone of her voice when she says "I'll see you after you close," she is insinuating that it is a known fact that he is closing. I own the DVD and was watching the deleted/edited scenes and that scene was originally supposed to come after the scene where he finds out that he's there for the night.