How to deal with mold on pickle?
If your solution grew mold, it would indicate that either the container wasn't sufficiently sterilized before sealing or (probably and) the solution wasn't sufficiently acidic. This can usually be ensured by following a recipe that is known to be good, which should have factors like acidity and water activity accounted for.

As for kahm yeast, it seems that this occurs more frequently on cultured vegetables which would spend some of their time in a less acidic environment (while the culture develops and acidifies). I suppose you could culture it and test it, but when in doubt I'd just toss it.