Feeling ****** by old mutual

I had an funeral policy for my brother. He died of gun shoot and it toke 2 years of investigation by the police officials and they couldn't find who shot him. The ****** case was then withdrawn and the magistrates ruled that he didn't found my late brother capable of his own death. Yet old mutual is insisting that he committed ****** and they said they not gonna pay out the policy. I asked them to send me such proof as a family member but they have been quiet since then.