I would suggest that either your attorney gave you bad advice or there was a misunderstanding here. There is no exception for federal retirement plans from equitable distribution from a divorce decree.
Additionally, even if there were, your divorce judgment provides for your former husband to have a 1/2 interest therein. When the judge did that, he did so as part of a total equitable distribution scheme. In other words, if your former husband did not receive any interest in the retirement plan, he would have received a greater interest in some other marital property.
I wish I had better news, unfortunately, your former husband is entitled to his share of this account. Sorry.
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