I was looking through the various files archived in the epub, and I found out that the book is a series of html files, so I looked at one. I noticed that there is no annotation where the fonts would change <font face...>. So I assume that wherever the font would change I would have to manually put in the <font...>.
If that is the case, it would not be worth the trouble. An embedded font would be worthwhile if the whole book were in that font, such as Hindi or Bengali, but not where the fonts alternate.
If this is the case, I will be satisfied with the PDF version. iBook is good with PDF.
My thanks to the people who wrote in, and I apologize for taking your time for nothing.