Vanguard suggesting amending the 2021 tax return is in regard to the 2022 Form 1099-R with codes J and P. Any amount in box 2a of this form is taxable on your 2021 tax return and would be the reason that you would need to amend, but since that amount is zero, you do not need to amend (unless your 2021 filed tax return reported an excess Roth IRA contribution on Form 5329 Part IV that now needs to be removed).
It's not clear how much contribution was actually returned with respect to each of these Forms 1099-R because box 1 shows the amount distributed, not necessarily the amount of contribution returned. If box 2a shows a nonzero amount, you can infer that the amount of contribution returned was the box-1 amount minus the box-2a amount. However, if box 2a is zero (or, mistakenly, blank), the amount of contribution returned could be more than the amount distributed as a result of investment losses. Your husband's 2021 and 2022 Forms 5498 would likely be needed to determine the amount originally contributed.
