Thanks again for the help! Johnny, it's $130 or more per person for the jab here in L.A. I'm guessing they keep it cheaper in S.A. so that people will actually get it and not spread the disease. We are considering getting it in Lima so that we'll have it for future travels, but it won't do us any good if asked for a certificate on this trip since they aren't valid until 10 days after getting the jab.
Everything I've found online says there is no risk of YF in the Galapagos.