Excellent news! Bill Thayer has been adding to his Diodorus Siculus pages: The Text of Diodorus Siculus on LacusCurtius.
He explains the background here. This means that we now have Books 1 through 32. Quote:
Still, this pseudo-end of Diodorus is in the best tradition of ancient texts: after managing to write soberly for 3000 pages, he finally caves in and concludes Book 32 with a rather long tale about hermaphroditic prodigies, unnatural intercourse, and the biology of the hyena: enjoy.