Where did you get her from and how long have you had her?
So fair there are no known variants of Princess Pearl, other than the German exclusive.
There aren't any Princesses with glow in the dark symbols. There are a few with glow in the dark hair though
Princess Amethyst and Princess Sapphire variants.
It sounds like the silver coating has worn away, I have seen this quite a few times. Harsh cleaning product and thinks like Oxy-Clean will strip the metallic coating off.
Love pkw xxx