Follow the money.  Does he have constructive receipt, or is it just sitting there in her account?  It is up to the successor trustee to take care of this.  You can't appoint yourself and you probably can't practice law in your state without a license.  

If he received the money, put it on his return and figure out how to get him help this year.  If he did not, follow your conscience.  Another reason why trusts are a mistake for far too many people, who never find out because they're dead by the time it becomes obvious.