Basically this situation was no ones fault unless the resturant purposely gave chicken with tons of bones in it. Its a tragedy and im glad the guy survived.
I work as a work health and safety advisor, the purpose is not to lay blame but to identify the hazards and access the risk and then mitigate that risk.
The hazard in this case was the bone, the risk of that of a chocking or internal injury.
Two levels of mitigation are required and eliminating the risk is most desirable.
The first level would be to determine if it is practicable to remove all the bones
The second level is a fail-safe for the first, that is to determine if a bone is present before it is swallowed.
So an incident happened, there has to be a failure in the process, if the bone passed the two levels of mitigation.
There would be other solutions available.
Litigation is an intent to lay blame.
Regards Tony