Wait — I think you’re getting a bit confused. Only retirement accounts and insurance policies have beneficiaries! But most financial institutions will issue CDs in the POD format — payable on death to the named person. And in that case you would definitely need a death certificate and “papers” to prove you are the person named as POD. So whether you are a named beneficiary of say an IRA CD or just a POD recipient, you’d need the same papers. You’d just have different options on what to do with the money (IRA beneficiaries may be able to roll over and stretch out withdrawals, leaving some money to continue to grow tax deferred).
I’m guessing these “papers” — required in every bank — are what this bank is saying. Double check.