I am glad you have a School Governor and a Teacher responding to your post. It would have helped us if we had had that in our case. I would recommend consulting a solicitor as well, and do make sure that everything is backed up in writing.
My son was also hospitalized by a child at school this year, luckily he appears to have made a good recovery but until he finishes growing we don't know exactly what the long term effects will be.
Look at the School's Health and Safety Policy, that should state whether or not they have to inform anyone else. As your child was hurt at playtime, as was my son, it is unlikely that it has to be reported to RIDDOR but they should report it to the Local Authority.
I have found that the Coram Children's Legal Centre is really good for giving free advice to anyone without a solicitor acting for them too. If you can't get through (lines are always busy), then leaving a message outside of hours does get you a call back.
In our case, we made a complaint but the School Governors did not take it seriously, you cannot rely on them to do the right thing unfortunately.
It sounds as if your son actually has a life-changing injury, luckily, my son's wasn't thanks to the skill of the doctors in A&E. Take the holidays to do some research online, but use your position, I would not want to let me child back into a situation where he felt unsafe, or I felt he was unsafe and you may be able to use that to make sure it isn't him that has to move.
Take care of yourself and your child, this kind of thing is really horrible, I know my son had to learn some pretty hard lessons in life from what happened to him this year, and so did I.
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