Both of them talked for sometime or you can say Jenny was the person who asked many different types of questions to Allen and he was just answering some of them. After sometime talking like this Allen already finishes food and then says goodbye to her and leaves the cafeteria.
As you know that he wanted to avoid Jenny and the other top 10 students that could make him in the spotlight once again so naturally he will stay away from them. Previously new that he would meet her inside that room then you will never enter the room but then what can he do in that situation?