I don't practice in WA, so you should consult with a WA attorney for specific advice on your situation. Generally speaking however, if you have a divorce agreement that covered the distribution of your marital property, then it is likely that you could return to court. In my state, most - if not all - agreements contain language that each party has made a full and accurate disclosure of their financial assets and debts, etc. You may want to review your agreement if you have one and see what specific clauses are present.
This would not likely change the legal status of your divorce, meaning that of you are divorced now you would remain divorced despite the financial issue. It could certainly change how the property was distributed, depending on the details of your situation of course and the laws in WA. Sorry I cannot be more specific!
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