You need to use the camera connection kit or use a lightening to USB from Apple to connect direct to your camera to successfully import raw files to photos.
What is happening is that your raw photos are being imported into the photos app as jpegs, even if they don't exist as jpegs on your camera !. Don't go via iTunes, pretty sure that won't work either, and currently WiFi camera access at least on my Canon 1300D does not support RAW import and does an automatic conversion to jpeg.
When you import from photos, your raw files will be marked as RAW on each file, if you do not see the word RAW then you have not successfully imported your photos in RAW format.