Final answer:
Jane wants Ender to go to Lusitania to add another volume to The Hive Queen and the Hegemon, which she believes is a significant contribution.
Step-by-step explanation:
Going to Lusitania is important to Jane because she wants Ender to add another volume to The Hive Queen and the Hegemon, which seems to be a book she holds in high regard and believes Ender can contribute to. The text suggests that Jane has a motive and a deep respect for Ender, which leads her to take this step. It is not explicitly stated why the volume is important to her, but it can be inferred that she values Ender's talent and sees his contribution as significant.