My advice to you would be to give him everything that he has asked for.
With regard to claiming on your own insurance, you are not actually obliged to claim on your own insurance. This incident is through no fault of your own and there is nothing you could have done anything about and hence, there is no reason why you should want to involve your own insurance company unless the other person does not have insurance or is financially worthless or there is no one way of knowing who is actually responsible.
I suggest you reply why you are not submitting a claim to your insurance company is that the leak came from his property, he is liable, and hence, you are claiming from him. If he refuses to deal with the claim or to pass it to his insurance company, then you sue him personally and it’s up to him whether he then passes it onto his insurer or not.
Can I clarify anything for you?
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