Honestly, I don't know if they're in the camera roll or not, as there is nothing on here that says as such. They're simply marked "albums' and 'imports'. No "camera roll".
There are three other albums saved in the iPad that the computer seemingly cannot "see" to import.
Only the photos taken using the ipad camera can be transferred to the computer directly. (the photos in the ipad camera roll).
The other photos cannot be transferred directly.
So if the photos in the camera roll are all transferring to the computer, then it is working fine.
Are all the photos taken using your ipad camera?