No wrist slapping
You will find that the Air Navigation Order has a get out clause that allows the commander of an aircraft to deviate from the ANO If life is in danger.
I think that landing a light aircraft in a field to aid the victim of an accident would be such a situation.
No doubt there will be some who will be critical of the pilots actions on all sorts of grounds but I can only commend his quick thinking and common sence and am sorry that despite his actions the situation did not have a more successfull outcome.