Or her lawyer enlightened the customer that her giving her account card to a third person was a liability and she won't get away completely blameless in the matter. Assuming the person falsely receiving her balance receipt had to have her card to make that deposit.
Why would anyone need a card to make a deposit at a teller?
I'm glad its resolved but I do understand why the customer might have mentioned their lawyer.
I know a guy who for whatever reason never had checks specifically available to pay his child support. But he had the money and loved his kids and had no issue paying on time, sometimes even paying more. So he would go directly in person to the bank and deposit the cash into his ex-wife's account.
I can certainly see how, in case like that, the account holder would be very upset to have the depositor know the account balance., and why perhaps it could be a legal matter requiring a lawyer's intervention.
(After years of this she one time threatened to sue him for not paying child support. She knew he had no cancelled checks or transfers out of his bank account to prove he'd paid. Of course, he calmly let her know he did have years worth of receipts from the deposits showing he not only paid, but paid more then he'd be ordered to. She let it drop. But none of his receipts, to my knowledge had her balance on them.)