A reportable rollover indeed happened. The partial distribution that you received that was originally intended to be part of your RMD for 2020 ceased to be any part of an RMD upon the CARES Act becoming law. Whatever you did with it must be reported as if it was not an RMD (because, by law, it was not an RMD).
The amount of tax withholding reported in box 4 of your Form 1099-R is credited back to you on line 25b of Form 1040.
