Your summary is confusing. I do not know how your disclaiming YOUR interest has any bearing on it going to someone else. Are you saying that you have a creditor (or perhaps a husband), that might find a way to get an interest in the asset, if you do not disclaim? If that is the case, then you can certainly disclaim the property. If you do not have an interest, then you cannot disclaim. You lost me in the indefeasibly vested section, as well. If you are concerned because you have not filed a timely disclaimer, then you should speak with an attorney to see if there may be a way to remedy a late disclaimer.
If what I have suggested is the reason you are considering a disclaimer, you should speak with an attorney to make sure you do not have better options. Getting rid of the inheritance is pretty drastic insurance.
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