You didn't explicitly say, but I assume the 2009 contribution was your contribution. It's also not clear if you believe that your 2009 joint tax return failed to include your 2009 From 8606 or if you simply are unable to find a copy of the form that was filed. If you believe that it was filed, there is probably no reason that you actually need it as long as you know the amount that would have been on line 14. The maximum contribution for 2009 was $5,000 ($6,000 if age 50 or over).
You said that your 2020 and 2021 Forms 8606 showed the correct basis, but did your 2020 From 8606 include the basis from what would have been on line 14 of your 2009 Form 8606?
If you believe that the 2009 Form 8606 wasn't filed, you should be able to file it stand-alone using your current name and address, although I think it would make sense to include an explanation that provides the information about how the 2009 tax return was filed. Trying to file it along with 2009 Form 1040-X could be problematic due to the 2009 tax return having been a joint tax return. IRS processing offices may have changed over the years, so I would probably send it to the IRS office where you would send a 2022 tax return that did not include payment. Given that how long ago this form should have been filed, the IRS will probably assess a $50 penalty for the late filing of the form.
I f you are unsure if the 2009 From 8606 was filed, your other option would be to assume that the form was filed and provide explanation if the IRS ever questions your calculations on Forms 8606.
See Penalty for Not Filing and Overstatement Penalty in the instructions for Form 8606:
https://www.irs.gov/pub/irs-pdf/i8606.pdf
