According to the Taxpayer Certainty and Disaster Tax Relief Act of 2020 in December, it states that the Act allows taxpayers to report earnings from either 2019 or 2020; whichever year that provides the highest tax credit. The wife did not have any earned income at all for 2019 so she didn't even file a return.
Yes, you can use your 2019 earned income instead of your 2020 income to compute the Earned Income Tax Credit if your 2019 earned income was more than your 2020 earned income.
If your 2019 earned income was lower than your 2020 earned income because your wife did not work then you will have to use your 2020 earned income.
Please see What are the qualifications for the Earned Income Credit (EIC or EITC)?
Please follow these steps in TurboTax to use 2019 earned income: