I am not privy to his will, estate, or trust, so anything I do would be idle guessing. Sorry. My assumption is that it is locked up for 100 years or more after his death, which would make it unavailable until 2110 at the earliest. We’ll all be dead by then. My surmise is that he didn’t want any living family member who lived contemporaneously with him to benefit from (or be in any way touched) by his writings.