Your last step, after all the corrective distributions, is to take a regular distribution of $6000 from the Roth IRA. That represents the removal of the excess from 2019. You have to take it as cash, you can't take it in-kind. What you do with it after that is an entirely separate issue (put it in a bank, or regular broker account, or buy rare Air Jordan sneakers, it doesn't matter).
For the amended 2019 return, you need to report the 2019 Roth contribution. If, based on your income and other situations, the contribution is considered excess, then Turbotax will ask you if you plan to remove the excess by April 15, 2020 (because the software is still stuck in 2019). You will say "no", and Turbotax will calculate the 6% penalty on form 5329. You won't get anything from the broker for this.
In fact, it seems you did not report the contribution originally on your 2019 return or this would have been caught already.
For the amended 2020 return, when you report the 2020 contribution, the program should warn you it is excess and will ask if you plan to remove it before April 15, 2021, you will say yes, and when it asks how much you will remove, you will indicate the entire $6000. (This is what will be reported on your 1099-R when you get it.). You don't report the appreciated amount removed, just the principle amount removed. On your 2020 return you should also be asked if you had excess from a prior year that was not corrected, you will report the $6000 from 2019, and Turbotax will calculate another 6% penalty of that amount. (Normally this would carry forward but it won't in your case since you already filed a 2020 return and you can't link the form 5329 from the amended 2019 to the amended 2020, so you will have to enter that information manually.)
Here are the amending instructions
https://ttlc.intuit.com/community/amending/help/how-do-i-amend-my-turbotax-online-return/00/27577
https://ttlc.intuit.com/community/amending/help/how-do-i-amend-my-return/01/27439
