You need to retain an experienced family law attorney immediately. The court has already granted 2 important requests of your ex husband and your side needs to be argued now. Don't attempt this on your own.
If you have an ex, then you should have a parenting plan (if in Washington). If that is the case, then bring your parenting plan to an attorney's office in your county for review of paragraph 3.14, which should be labeled "RELOCATION." If you do not have a current WA parenting plan, then I would give =written notice that you plan to leave the State because you need to relocate for employment reasons. The confusing part of your question is that you say that you have "kids" (plural), but custody of your son. This can be cleared up in your first attorney-client meeting. Curios - what county are you in, what court signed the parenting plan, and who is the attorney that said he will get full custody if you leave the state? (which is not correct).
Your custody order would be subject to Washington's RElocation Act. RElocations are complex and should not generally be attempted without counsel. Seek a family law attorney immediately. You can also discuss with him/her options to modify the no contact provisions of the restraining orders prior to the full hearing.
This post is not meant to be legal advice for a specific situation. Additionally, it does not constitute an attorney client relationship. It is always recommended that you consult with the attorney of your choice before taking action which can affect your legal rights.
Sign up to receive a 3-part series of useful information and advice about child custody law.