Yep. He was much more interested in the mockingbirds - after all, that was a better example of his thesis. 9 species on 9 islands, no hybridization, etc. The finches are a great example of adaptive radiation, but less so in the sense of speciation since they mix and match between islands and it probably wasn't until the Grants that the relationships were really worked out.
I'm impressed that you translated
Origin into Indonesian - that must have been a LOT of work. "Labor of love"?