Don't doubt it. It is accurate. His indictment and conviction are vacated, as are any fines or restitution orders imposed as part of his criminal case. It is as though the criminal case never happened as far as the law is concerned.
Civil cases are another matter. What will or will not be available to satisfy a future civil judgment is a matter of Texas state law, but you should not assume that all of Lay's assets will be available to satisfy a future judgment in a civil case. Many of those assets will pass to heirs as a consequence of his death, and it is not at all certain that future creditors will be able to overturn those transfers.
Uh huh. And there's no way to determine which of the gains passed on his heirs are stolen. In the eyes of the law, his heirs get their proceeds and I doubt creditors have a leg to stand on. I'm sure Lay took great care for this kind of contingency. Its a dry hole as far as those seeking restitution are concerned.
(The Palestinian terrorist regime is the crisis and Israel's fist is the answer.)