[Pit1]

Can someone let me know if the FBI can get involved? I would think this is up their alley. If not, what law enforcement agency has control over this type of investigation? And what about the agency where he filed his papers to run???

[Red Steel]

You could start here on what to do: Statute Of Limitation Forgery
"If you have a document where the authenticity is in question... I can help you."

[Polarik]

ICE.GOV, or Immigration and Customs Enforcement would be the agency that handle immigration violations, applications for entry into the US, etc.