You cannot include the checks that were cashed in 2024 in your 2023 RMD. The money was not withdrawn from your IRA until 2024. The amount shown on the 1099-R is the total amount that you withdrew from the IRA in 2023, and there is nothing you can do to increase it. If the amount on the 1099-R is less than the total amount you were required to withdraw (your RMD), then you did not take your full RMD in 2023. However, you did take the remainder of your 2023 RMD in early 2024.
There is normally a penalty (technically additional tax) for not taking your full RMD. You can avoid the penalty by requesting a waiver from the IRS. The waiver is almost always granted automatically. After you enter your 1099-R in TurboTax, continue through the questions. It will ask if you took all of your RMD. Answer that you did not. It will then ask for additional information to fill out the Form 5329 to request the waiver. You will not be charged the penalty, because the assumption is that the waiver will be granted.
One of the things you have to enter is a brief explanation of why you didn't take your full RMD and what you did to correct it. I would say something like "Checks written from IRA in Dec. 2023 were not cashed until Jan. 2024." I would not mention that the checks were QCDs. It doesn't really matter, and might cause confusion.
The checks that were not cashed until 2024 will be included in your 1099-R for 2024, so you will pay tax on those withdrawals on your 2024 tax return. You must still take your full 2024 RMD in addition to the checks from 2023. Your 1099-R for 2024 will include the delayed 2023 checks and the full 2024 RMD in a single total.
