Where TurboTax says that you can use the year-end statement, that's referring to documentation that only corroborates the amount deposited into the IRA that you might need to indicate in TurboTax as the amount of the distribution rolled over (because it could be the case that not all of the distribution was rolled over).
The distribution from the 401(k), whether rolled over or not, is required to be reported on a Form 1099-R that is required to be entered into TurboTax and is the only way that this can be included on your tax return. Contact the 401(k) plan to obtain the missing Form 1099-R that they were required to make available to you no later than January 31, 2024. During the entry of this Form 1099-R reporting the distribution from the 401(k) is where you must describe the nature of the rollover.
