First thing I would do is ask your customer WHY he started asking these questions. Did he hatch out an unexpected axanthic? If so, does he know what line of axanthic because the other animal was from a known axanthic line?

Your female looks grayer than the other normal in the pics, but no grayer than one of my normals. Of course a lot depends on lighting in the pic, as well. But even if she is not axanthic, there is a chance she or the spider you paired her with are het axanthic.

One other possibility, depending on what your customer was working with, is that I've heard of a line of albinos that the het albinos often look axanthic as hatchlings, then turn to normal colors after a few sheds. I don't remember much else about it, and some people in the thread were calling BS, so I'm not even sure it is real, but it would be a possible way unexpected "axanthic" hatchlings would show up.