Legal Question in Wills and Trusts in California

Maybe. If, for example, the decedent intended that the POD account to be reimbursement for those expenses, with perhaps a little on top of that for good measure, then it's certainly reasonable for the trustee to deny such a claim from a beneficiary who has already been paid off. The devil is in the details though and depends on how much money is there in expenses, how much was in the POD account, and what proof exists that the decedent intended the POD account to be used for expenses - it's actually fairly common to do so.