When TurboTax asks how much RMD you received, all $91,000 counts as part of the RMD that you received. Entered correctly into TurboTax, all $91,000 will be included on Form 1040 line 4a but $90,000 of that will be excluded from the amount on line 4b with the notation "QCD" next to the line.
Why do you need Form 5329? You don't need a waiver if all you did was take your MRD as QCDs. After you finish entering your 1099-R and continue through the questions, you will come to a screen that asks if you transferred any of the distribution to charity. You will enter the total amount of the QCDs, and TurboTax will put the notation "QCD" on Form 1040 line 4b. That's the only explanation that's needed.
You only need Form 5329 if you did not take the full MRD amount, or if you made excess contributions to your IRA or took an early distribution before you were 59½ years old.
When TurboTax asks how much RMD you received, all $91,000 counts as part of the RMD that you received. Entered correctly into TurboTax, all $91,000 will be included on Form 1040 line 4a but $90,000 of that will be excluded from the amount on line 4b with the notation "QCD" next to the line.