Why would you expect a lawless organization like this to actually pay you?

It might just be easier for them to say "Thanks, but we already knew that, and by the way that's ultra classified so we'll give you the option of a clean suicide."

Because the "lawless organization" is backed by the richest country in the history of the concept of money.

The money isn't the issue. The issue is that once you disclose the algorithm, your continued existence can then only represent future nation-state levels of liability.

The NSA isn't some faceless villain. They are an organization that has been consistently 10-20 years ahead of the world in many math disciplines.

The NSA is but one of several massive spy operations under the Pentagon. It's not even the best funded. Several of them are ones most people have never even heard of. I'd say that qualifies as 'faceless'.