1. Magick has no color and as such your magick is defined by your actions. To put it another way magick is "colored" by how you use it and the way you treat others.
2. Grey or gray magick is the belief in a form of magick that falls between the categories of black & white, good & evil, etc... Despite their lies if the casters goal was to help someone it wouldn't be considered grey/gray if magick did have a color. In the end though magick is not as I have stated truly categorized by color as one can turn the nicest of things to dark and vice versa.
3. As previously stated karma is a concept not everyone believes in and technically karma is often referred to as someone being punished in this life when the actual definition of karma involves the concept of reincarnation. In the end I like to believe people reap what they sow including myself, but at the same time I'm not certain of the severity of their transgression of lying about one's own health condition. People lie and that doesn't often rain down bolts of lightning though they make receive their just deserts in the end.