"The executor (one of the 6 beneficiaries) filed the deceased tax return and paid taxes on the IRA and Capital gains along with her SS taxes, etc. on her 2022 return."
As others have said, this IRA and capital gains income is in respect of a decedent and was to go on an estate income tax return, Form 1041, not the decedent's final tax return. It seems that the executor has made substantial errors if this income was reported on the decedent's final tax return. Whether this is 2022 income or 2023 income depends on whether the estate uses a calendar year or a fiscal year for reporting income. If it uses a calendar year, the 2022 Form 1041 is late, subject to substantial penalties for being late. If the estate uses a calendar tax year, the home sold in 2023 would go on the 2023 estate income tax return, not the 2022 estate income tax return that was to include the 2022 IRA income and capital gains income. It might be beneficial for the estate to use a fiscal year for its tax year, which might not yet be due depending on when the IRA was distributed and the stock was sold, making this 2023 income to the beneficiaries passed though on Schedules K-1.
