Not surprised in the least.
Brazil's President probably isn't accepting this because he doesn't want to look weak from within his country. People looking at this from the outside can't understand this, as all they're thinking about is saving the rain forest -- but in the mind of Brazil's president, he can ignore that and continue his strongman image and pro business image.
It's a very weird thing to look at from the outside. But I can without a doubt see political enemies saying that he's weak because of the fact that he accepted aid from other countries and was unable to handle the issue himself. There's also the problem of different countries wanting a favor back (not in the news) from their monetary aid.