He might be infected with a communicable disease that won't be expressed for a few more days. Being wheel-chair bound is a liability when you need to move fast. It requires extra helpers to apprehend and move him. A perfect mule for a bio weapon --OR-- perhaps he's just a helpless old man who is ready to retire his association with OBL. A two week quarantine would be prudent and harmless.
You're getting as evil as I am.