@Carl seems to think the credit is a gimme. Maybe that's the voice of practical experience. I tend to assume that when people put things in writing, they more or less mean what they say.
I can't judge the legal merits of your situation but it seems like a fair case and I don't have any reason to argue with Carl other than my own natural skepticism.
I do want to make two final points, though. First, the itemized deduction method is available for any repaid wages, even if the claim of right method was disallowed by an auditor, you could claim the repayment as an itemized deduction and claim at least some tax benefit. Second, you should not assume that the tax credit method gives you a better recovery. You are allowed to figure the tax effects of the repayment both ways (as a credit applied to 2020, calculated from 2019; or as a deduction in 2020) and use the method that gives the largest recovery. I could create hypothetical situations on both sides, so the only way to know for sure in your case is for you to test it both ways. (None of this affects how you must first file your 2019 return, of course.)
