I don't know about that.
I do know that unless a country or territory is under the governmental control of the USA, it's not "under the flag" of the USA. That means, the US doesn't have authority over the laws of that country.
By statute, the US does not allow slavery. That doesn't mean that there aren't cases of slavery occurring but it means it's not sanctioned by the law.
Those under the flag of the USA would be the United States (of course), Puerto Rico, Guam, U.S. Virgin Islands, American Samoa, Northern Mariana Islands, Midway Islands, Wake Island, Johnston Atoll, Baker, Howland and Jarvis Islands, Kingman Reef, Navassa Island and Palmyra Atoll. Overseas embassies and military bases would be included, too.
Personally, I don't want my country sending monetary aid to any countries that allow slavery to continue.
