The question is answered. What lacks is a judgment call.
BTW, I am in complete agreement:
"This was not the first time the tyres of the Concorde has damage from impact, nor the first time this type of metal had been found on a runway. It was not unreasonable for them to foresee such an occurrence. It was negilant to operate an aircraft in such a manner knowing it was susceptible to this issue but not take action to avoid it."