For what purpose does Oona go to Cairo in the novel, Oona Out of Order?

When Oona first finds the display case of tchotchkes (travel mementos) she has no recollection of collecting them. As the story progresses, she finds the source of the knickknacks and travels to Cairo because of the Egyptian figurine in the case. The reason for her travel is avoiding her meet-cute with Edward but she discovers that they met on the plain to Egypt and learns that fate cannot be outrun.