Actually, thinking it over, "his" agreement may not stand up if pressed, since they've alledged he's incompetent. On the issue of incompetency, you should prepare yourselves for the money being stopped until the issue is resolved and knowing the VA that could take many, months.
On the issues of HB & A&A, he should file, ASAP, and I would use the original claim date as the date of onset. There may be an open claim if the matter wasn't discussed when he was awarded 100%. jmo
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