It's laughable that the files are "lost"....The entire Library of
Congress by some estimates is 200 terabytes. Go to Amazon and look up flash/thumb drives. You could fit the entire library of congress in your pocket for less than $100. Text takes the least amount of space. Data recovery techniques can recover data that's been overwritten several times. It's most likely they have online backup of all of their files for years, not to mention paper copies.