You can take @RobertB4444's first two suggestions. Unless you're successful in having the bank issue a corrected 1099 with zero amount for the account that belong to your ex-wife, you do need to report the amount of interest income on your tax return and then back it out on Schedule B, labelling it "Nominee distribution". Yes, the IRS would want you to issue your ex a 1099-INT for that amount, but even if you don't, I highly doubt the IRS will go after you.
Regardless, you should let your ex know and advise her she needs to report that amount on her tax return. You should also advise your ex to contact the financial institution to change the name and SSN to hers.
