EIP3 Question - Taxpayer Claimed as Dependent in 2020 but not in 2021 - Eligible?

[gfizer]

My son married in July.  His wife was claimed as a dependent on her mother's 2020 tax return and her mother received the $1400 EIP3 for her as a dependent.  Now that they are married they will file jointly for 2021.  Am I correct in saying they are eligible to claim the recovery rebate credit to get the $1400 for her even though technically her mother already got her EIP3 payment?  The FAQ's on the IRS website seems to indicate so but I just want to be sure I am interpreting this correctly.

IRS FAQ - 

"Dependents:  I didn't receive the Economic Impact Payment because I was claimed as a dependent on someone else's 2020 return. Can I claim the Recovery Rebate Credit if I'm not a dependent in 2021?

A9. Maybe. If you were claimed as a dependent on someone else’s tax return for 2020, you were not eligible for the third Economic Impact Payment. If no one can claim you as a dependent for 2021 and you are otherwise eligible, you can claim the 2021 Recovery Rebate Credit on your 2021 tax return."

[Pacun]

Yes, you should claim $1,400 on line 30 on their jointly return provided they don't qualify as a dependent for 2021.

[Randall]

And am I correct to understand the parents don't have to pay it back?  I know this was the case for EIP1 and EIP2.

[Pacun]

The only payback provision is for Advance child tax credit. All stimulus checks are not re-paid.