Actually, he should feel lucky. As a high functioning quadriplegic, his life expectancy was already quite low. Remember Christopher Reeves?
It’a win that cancer knocked him down rather than complications from his condition.
You are correct. Most quadripledics don’t make it more than 10-15 years after their injury.
Yes, there are so many bad things that can happen.
Many people watched him on TV for years not even realizing he was quadriplegic.