Alright I was hopeful I had solved the problem, but it appears not. Here's what I did. I replaced the system iconv with gnu-libiconv, so that when I did "iconv -l" I can see MAC ROMAN as an option. I did a new clean build of fontforge. When it was configuring I saw lines saying that it was going to use my system iconv instead of the light version they use if it's not on the system already. That seemed good because I just replaced the system iconv with a better one. Then I did a clean configure and rebuild of lilypond. But alas, at the same point I got the same message and it hanged.
Are there any other thoughts on how to get past this?