This is a meeting where billionaires get together to conspire, regardless of their supposed intentions, they are working together toward the same goal. It is a conspiracy. And they do it in secret.
Conspire
2. to act or work together toward the same result or goal.
“This is something so nightmarish that everyone in this group agreed it needs big-brain answers,” said the guest. “They need to be independent of government agencies, which are unable to head off the disaster we all see looming.”
Why all the secrecy? “They wanted to speak rich to rich without worrying anything they said would end up in the newspapers, painting them as an alternative world government,” he said.