ICloud – Can’t access RAW files in Photos.app

I cannot access RAW image files in Photos.app. I have a bunch of RAW files from both my Olympus OM-D E-M5 and from my iPhone (I use the Halide app to take them). They are all JPG/RAW pairs.

The photos display with the little J icon in the top right corner but the Image > Use RAW as Original option in the menu is greyed out. I'm pretty sure I had this working in the past.

If I dig into the Photo Library with the terminal I can see that the ORF (Olympus RAW Format) and DNG (Digital Negative) files are there. I just cannot access them from Photos app.

My library is an iCloud Photo Library and on iOS if I use apps that know about RAW files, such as Darkroom, they are able to open the RAW versions. I have "Download Originals" configured on my Mac.

I'm on Mojave 10.14.6 and Photos is Version 4.0 (3461.7.140)

Some things I investigated:

If I create a Smart Album with Photo is RAW as the only criterion, it only shows me a fraction of all my RAW files (170 images). Curiously, the ones that are JPG/RAW pairs show with the R icon in the top right corner but for these I cannot choose Use JPEG as original.

However, if I count the actual number of RAW image files in my photo library folder I have 1189 RAW files:

➜  ~  cd Pictures/Photos\ Library.photoslibrary
➜  Photos Library.photoslibrary  find . -name "*.ORF" | wc -l
     416
➜  Photos Library.photoslibrary  find . -name "*.orf" | wc -l
     550
➜  Photos Library.photoslibrary  find . -name "*.dng" | wc -l
     223

The only thing that "works" is File > Export > Export Unmodified Original from the menu, which correctly exports both the JPG and RAW versions of any image marked has having both.