If your parents already paid 18000 and can’t get it back it’s not fair to them to try and go to seminary and make them pay that money again. That being said you must go to a din torah ( or better yet an American court if they have any type of American arm) and you will win despite what you signed.
to torah613torah- When I was a child my Parents ROV had very little to do with me or my siblings getting in to schools , seminary’s shidduchim etc. At most they received a phone call checking me out for a shidduch. Nowadays Rabbanim spend half their day advocating for their misspalleims kids to get into school, seminary camp etc. And when it comes to shidduchim it’s unheard of the amount of time a good Rov who cares about his missplallim has to spend dealing with it.