I have seen one very strange thing. Your metadata item "Description" seems to use both html tags and smart quotes in it. This is true for both books you have sent.
I have never actually seen a book with html tags used inside of a metadata field.
Could you try deleting the html tags from the "Description" and use dumb quotes and see if the Kindle Fire still gives you trouble.
Value: "<div><p><em>I put it to William, particularly, that if you find someone you love in life, you must hang on to that love and look after it. . . . You must protect it. </em>