First of all a big thank you for the outstanding work! Does Caltech have any plans to release the LaTeX source? And would a PDF or EPUB be made available (free or otherwise)?
Did you mean "has not authorized"? Otherwise, I would gladly pay for PDF editions of the 3 volumes. If they already went with producing a free online copy of the 1st volume, I don't see why they should be against selling official eBook PDF editions for people like me who prefer to read this offline.
Anyway, great job on the conversion, it looks marvelous!