If your modified AGI for the purpose of being able to deduction a traditional IRA contribution permits, enter a proposed traditional IRA contribution and see. It appears that both of you are eligible to make traditional IRA contributions which, if deductible, would reduce the underpayment penalty.
If your AGI is low enough, a Roth IRA contribution might result in some amount of Retirement Savings Contributions Credit that would reduce the underpayment penalty.
