Welcome to the Lightroom Community. I'd love to help you figure this out.
Images synced from Lightroom Classic to the cloud are Smart previews. Smart previews do not consume space on the cloud.
Whereas full-size images are downloaded if you sync photos from Lightroom desktop or Lightroom for mobile to Lightroom Classic. So, if you've initially synced the Fuji Raw images from Lightroom classic, they'll only be available as smart previews on the cloud & other Lightroom surfaces.
As a test, try to import an image from Lightroom mobile or desktop uploaded as a smart preview on the cloud to overwrite the existing smart preview with the original image.
Let me know if this helps,