Embedded in the RAW file is a small JPEG. Since RAW is not a standard and can change from camera to camera, the JPEG is use to display the image. Google is reading the info of the JPEG.
You can extract the JPEG from the RAW file by using a program called "Instant JPEG from Raw". All the numbers should match with what Google sees.
that makes sense, thanks for the education. Why did they choose to sync the jpeg to drive though, instead of the RAW file? Is that a bug or a feature?