Rehired after layoff. Severance was a taxed lump sum. Have to repay the "unused" weeks of severance, it is calculated on pretax sum. Can I get the taxes back when filing?

Employer provided this, which I believe is straight from the IRS site "Employee reporting of repayment. The wages paid in error in the prior year remain taxable to the employee for that year. This is because the employee received and had use of those funds during that year. The employee is not entitled to file an amended return (Form 1040X) to recover the income tax on these wages. Instead the employee may be entitled to a deduction (or credit in some cases) for the repaid wages on his or her income tax return for the year of repayment." I need help deciphering this!