Pus isn't typically transparent. Pus typically contains white blood cells which give it it's characteristic color. Raw unheated honey will work better than pasteurized/heated honey. Pure isn't an issue. Pure translates to dead, inactivated honey. Honey is effective against many organisms, even antibiotic-resistant ones. If you use honey, I would try applying apple cider vinegar, before applying the honey layer. The skin normally has an acid layer that helps to balance the bacterial flora and immune responses that control inflammation. Manuka has the most press/research with honey, but other types work very well, also.
Are you treating your child's thrush with probiotics at the same time?