Just to update.... in case it helps someone else down the line...
Well, it wasn't the quick fix I thought it would be. The toc-preface was right on the other three sections. So it took a little bit more guess work to figure out what the heck was wrong with those books. I made copies - though I don't know why, it wasn't like I could make the situation worse!
- and started to work with them. I found two areas of concern. First was that somehow those had THREE style sheets. Two page_styles and one stylesheet. I deleted the copy and made sure that all the font faces went to the original one page_styles. (There were font face Droid and font face Droid_ul1 or something like that). So I got rid of all remnants in the style sheet and font folder of the extra.
Thought I was very clever and that would fix it. When it didn't I nearly cried in frustration but refused to come crawling back for more help - you had all done enough FOR me. I compared the fixed one to the other two and found that somehow, on the three that weren't working - and I am not sure how to explain this right - the @fontface in the page_style and style sheet CSS's were reversed. So they were both right, but in the wrong places. I copied and pasted the @fontfaces from the working doc and all fell into place!
Thank you again so much for all the help and to Hitch for explaining it in a way that made sense to a newbie! You are the best!