Spiders aren't white, but I have noticed that on each one the top of the head is lighter then on a normal ball, like they have a cap of lighter coloration on their skull. Perhaps this lowered amount of melanin could be a reason for the neurological condition.
However, I could be wrong, I just thought I would mention it because waardenburg's shows similar features in the varying degree that the animals are affected (some only a little and some severely), that no matter what the affected "morph" cannot be bred out of the condition (since it is actually caused by the color and not just linked to it) and how it affects the coordination, balance, ect of the animal. We can't really know if it affects hearing like in other waardys because snakes don't have ears.
Thank you for responding, I want to learn all I can and every bit helps.