Form 8606 Part III is not to be included in your tax return if the Roth IRA distribution is a qualified distribution, meaning that at the time of the distribution you were age 59½ (indicated by code T or code Q on the Form 1099-R) and it had been more than 5 years since the beginning of the year for which you first made a Roth IRA contribution. However, the distribution must still be included on Form 1040 line 4a (but excluded from line 4b) by entering the Form 1099-R into TurboTax and answering the follow-up questions. If you met the requirements for qualified Roth IRA distributions, it is improper for the IRS to have asked for the Roth IRA distribution to have been reported on Form 8606 unless the IRS disagrees with your assertion that the distribution was a qualified distribution (in which case what you need to provide is documentation showing that the distribution occurred after you reached age 59½ and after 5 years from the beginning of the year for which you first made a Roth IRA contribution).
If the distribution was not a qualified distribution (code J on the Form 1099-R or you had not yet the 5-year requirement which you correctly indicated to TurboTax if asked), then Form 8606 Part III will have been completed by TurboTax.
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