Good question. If one party enters into a written settlement of a lawsuit based upon false and fraudulent information provided by the other side, and it is later discovered that the information provided as an inducement for the settlement was false, the settlement possibly can be set aside by way of a noticed motion.The basis for doing so is that the "consideration" and basis for the settlement was made upon false representations and had the other side known the truth, the settlement as written would not have been entered into.In your situation, it is best to consult with an experienced contracts attorney that does civil litigation about what you have written about.