The fact is that your country's embassy-consulate must approve the waiver of the J-1 2-year return requirement. The fact that you have already been here on a J-1 for 4 years, longer than the 2-3 years that are the minimum before the 2-year separation is imposed indicates to me, however, that you already may have been exempt, which makes your concern about getting an extension puzzling. You definitely will need an attorney for this matter.
All answers to immigration questions should not be taken as legally binding advice. If you have an immigration issue, please call me at Pacifica Legal Services 805-290-4930 and make an appointment for an initial 30 minute consultation. Additional time is billed at $100.00 per 30 minute increments. Todas las respuestas a las preguntas de inmigración no deben tomarse como asesoramiento legal. Si usted tiene un problema de inmigración, por favor llámeme al Pacifica Legal Services 805-290-4930 y hacer una cita para una consulta inicial de 30 minutos. El tiempo adicional se factura a $ 100.00 por incrementos de 30 minutos.
Unfortunately none of that matters to the US, only your own country can waive the 2 year rule. http://travel.state.gov/content/visas/english/study-exchange/student/residency-waiver.html