I would say as long as the terms/limitations of the account are defined by the deposit contract and your Truth-in-Savings disclosures, you should be fine.
After all, our own government has the ETA accounts which must have direct deposit of SSI, VA, or SS benefits and can only be accessed by ATM card.
Certainly I would also recommend that you have your bank's attorney's/compliance dept. review the account agreement prior to offering the account to your customers
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