Max: My contribution via my Visa card is on the way.
If you are already incorporated as a 501c3 organization in PA, I see no need to further incorporate. You have your exemption from taxes letter from the IRS for the Foundation, right? Simply work everything through the Foundation. Wouldn't that make sense?
I am with those that don't believe your status as a non-profit will shield you from this kind of thing though. If they have a legitimate complaint, you may have no choice other than to comply with what they want or face litigation. Some good Attorney who also enjoys the fruits of the Mudcat could surely advise you how successful you might be, even if you could afford to defend yourself.