Have there been any other incidents with their dog?
On the face of it there isn't a case.
They could argue that leaving the door open was negligent which would create liability under the Animals Act 1971 but given that the whole incident was caused by their dogs offlead ran into your garden I would expect the reduction for contributory negligence to be 100%.
Can I clarify anything for you?
Well, however they got into the garden the point is that they were there and they had no right to be.
There isn't a contract.
Only to the extent that they could argue it is an admission of liability. It is not a contract.
If the insurance company are not willing to sue then usually that is because there is no case.
No problem and all the best.
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