Assuming that you are sure on your facts, if you want to spur IRS action, Congressional inquiries can often be helpful.  Ask your local Congressperson or one of your U.S. Senators to write to urge action.  If you live in a state where the Attorney General is active in assuring charity compliance with the rules, you can ask the Attorney General to make an inquiry.  The Attorney General will be more likely to help if you have a basis to allege some sort of wrongful misconduct and not a mere technical violation of tax rules.

If the 990-PF lists some, but not all, of the directors, you may be able to contact some of those listed to find out the others, or to get them to comply.  You may be able to ask grantees about who they know.  You may be able to search out the signer, who signs under penalty of perjury, or the preparer of the return.

If none of these channels works or you don’t want to go that way or wait that long, the real enforcers of charity compliance are the media.  Ask your local newspaper to do a story on the issue. It will be a better story if you know some of the directors, but they seem to be hiding others.  If a media outlet takes the story, it will undoubtedly ask the Foundation questions about the failure to disclose.

If no one in the media thinks it is much of a story, and if you really care, you can make it a better story by getting a group of people to picket with you outside the agent’s office, letting the media know in advance, of course.  You might get some TV time, and you might embarrass the agent who probably doesn’t want to be identified with an organization ignoring the law.