The correct answer to this open question is the following.
I can say that under the following conditions it is ethical for conservationists who live in the United States to lobby government officials in Brazil, Indonesia, and other tropical countries to slow the rate of loss of old-growth forests.
First, American conservationists have to use diplomatic approaches to use the correct language to ag¿ddress the issue and the political leaders of those countries.
Then, they have to fully understand what the situation is, knowing all sides of the story so they can avoid any mistakes. They have to include the official version of the governments to try to not bias their opinions.
Once they have done that, then they will have all the elements to make an official statement about the critical situation in those above-mentioned places.
And one very important thing, they have to be careful in using polite words such as "invite" or "exhort" when addressing the federal institutions of those countries.