
I would imagine most judges will be less aware of it thzan you and are unlikely to penalise her for such a cosmetic reason, unless they are presentaion mad.
My Champion bitch licks her paw every so often, and turns it orange. She does it sporadically so applying anti chew only works in stopping it getting worse. She usually does it after it has been nice and clean for a while, usually on the way to a champ show, sods law. Doesn't appear to have affected her show success, or maybe she would have done even better, who knows. :D
Take her and enjoy the show :D