Obviously you do not want to be in a possession of offering legal advice to your customer. Trust and beneficiary law vary by state so I would contact bank counsel to see which would take precedence.
That being said, the purpose of having a trust is to direct the successor trustee to distribute assets upon the death of a grantor. A trust is an entity and therefore does not die. Based on this fact, it does not seem appropriate to allow a beneficiary designation on this account since the trust document should stipulate what happens to the funds upon the death of the grantor. If Jane wants these funds to be distributed in a manner not consistent with the trust, then they should not be included in the trust assets (i.e. titled in her name only with a payable on death designation.)
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