Apparently Expert Raw should be supported on the Galaxy Note 20 Ultra, S20 Ultra, and the Galaxy Z Fold 2 within the next few months,should all go to plan. See some information here https://9to5google.com/2022/05/25/galaxy-z-fold-3-expert-raw-camera/
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
My Device- S21 Ultra 5G ( SM-998B/DS ) CSC= BTU , 12GB/256GB
One Ui 4.0,Android 12 Official Version.