I wouldn't say I trust them, but I would say it's the most likely explanation.
It could be that they've failed to understand how RSS could help their organization achieve its goals. But it's probably just that RSS isn't worth it to them.
I'd have to know which NGO and what their circumstances are to have a more concrete opinion. With no additional information, I can construct a hypothetical scenario where a reasonable site admin would yank RSS.
It could be that they've failed to understand how RSS could help their organization achieve its goals. But it's probably just that RSS isn't worth it to them.