My instinctive reaction was to laugh and say something along the lines of "Andrew McMahon doesn't need exposure", but then I took a step back and realized that's probably not true at all. =/
Anyway, I hope everything goes well for his family. Good on him for stepping back. Taking care of the family is much more important than playing a show. Most of his fans will understand. Those who don't are probably not the kind of people who deserve to see him anyway.