They are slightly pinkish. The proof though will be in the prints.

If you pull the image into Photoshop, choose the Eyedropper, choose a sample size of say 11 x 11 and run through the background you'll find

Red: 242
Green: 241
Blue: 236

The numbers change as you move around but the blue channel is consistantly 5-8 points less than the other two. For pure white / gray you want them within a couple or three points of each other.

Nice shots of a very rare and unusual pup.