Your 2020 RMD has been waived. You can still do a QCD, so your info is incorrect in that respect. Of course, you must have reached 70.5 to do a QCD, but it will not have the same tax impact because there is no RMD to offset. You will save more if you delay the QCD until January and perhaps double up in 2021 when RMDs resume. Those 2021 QCDs will reduce taxable income from the 2021 RMD. If you do a QCD this year, while the distribution will not be taxed, it will not change your taxable income for 2020 but it will reduce future RMDs by a small amount and save you tax dollars in future years, but not in 2020.
Instead, if you delay your QCD(s) until 2021, you will offset the increase in taxable income in 2021 due to resumption of RMDs.