I agree with your thought process. Putting the beneficiaries on the system could mislead an employee into thinking the account is set up as a POD and releasing the funds incorrectly. In many cases a trust can specify that the trustee must distribute the funds to the beneficiaries when certain conditions are met. (Example, Johnny gets $5000 on his 18th birthday, $5000 on his 21st birthday, and the balance on his 25th birthday.)
Simply listing him "on the system or on a signature card" could be very misleading.
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