Either pickpocket or kill her. Even though you should get the scroll, she most likely still has it on her. And you can get the book back for your personal use that way too
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The last arrow of Legolas kindled in the air as it flew,
and plunged burning into the heart of a great wolf-chieftain.
All the others fled. -J.R.R. Tolkien, The Lord of the Rings
