NGO means non-governmental organization. A Non Profit or Not For Profit status is assumed.
The Watchtower Bible and Tract Society of New York, Inc. properly belongs on any complete listing of active NGOs because they certainly are an active NGO. They have been since 1879 and will continue to be.
NGO is not a membership type. It does not imply affiliation with any other organization; it only describes the nature of an organization.
What seems to be confusing some people is that saying, "The WTS is still an NGO!" is akin to someone announcing about me, "AuldSoul is still a white guy of mostly Irish descent!" My response to either exclamation will be, "Yes? So what? That has always been the case."
Now the statement, "The NGO, Watchtower Bible and Tract Society of New York, Inc., was joined as an Associate member to the UN Department of Public Information for ten years!" is much more appropriate because there is some misconduct involved (according to their published standards). That would be like saying, "A white guy of Irish descent, AuldSoul, stole a wristwatch!"
In this case, saying that the WTS is an NGO is just stating a basic fact of the nature of the organization itself. Saying it was found in a list of NGOs only means that someone else recognized and noted the organization's nature, no matter whose list it was found in. If the NGO is a member of some other group, such as WANGO, then that becomes a different matter entirely. But there is no evidence on this thread that the WTS is a member of WANGO.
Mandy Patinkin as Inigo Montoya: "You keep using that word. I do not think it means what you think it means." (The Princess Bride)
Respectfully,
AuldSoul