The fuselage panelling adjacent to the props is reinforced to prevent damage by ice coming off the propellors. I don't know if it is designed to protect against damage from the prop itself.
Nope its not. Not only that but the size of the piece may be so large that even separation and redundancy of aircraft systems for flying may not provide protection. It's kind of like a big fan disk, you basically have to make sure they never fail on a flight that you are on. But I wouldn't worry about a worst case failure in a landing flop. Too much data saying ho-hum