You are certain that the 2020 deposit is for tax year 2020, and nothing applies to 2021. Because that matters. Everything matters. And you’re stating the 2020 contribution was removed in time for the 2021 tax return to be timely filed. That means the 2020 tax year filing was wrong and needs to be amended, or already has the Form 5329 in it? Because that’s the form to use for each year. What about tax year 2021 having Form 5329? There is the determination for penalty, excise tax, and/or income taxable earnings (depending on the details, age, etc) per year. Maybe 2021 needs to be amended.

There will be a 1099-R for the corrective withdrawal, dated in 2022, code P for prior year. You enter that same info into 2021, even without having an actual 1099-R, because that is the tax year the withdrawal was done for (not when done).

"If there is specific guidance out there for the second year of the over-contribution I'm not seeing it."

The IRS has it. Jump to Part IV for Roth Excess, for each tax year and work your way up:

https://www.irs.gov/pub/irs-prior/i5329--2020.pdf

https://www.irs.gov/pub/irs-prior/i5329--2021.pdf

https://www.irs.gov/pub/irs-pdf/i5329.pdf