1. The direct cause of the death of the deceased was electric shock.
The deceased got an electric shock because the power supply company failed to repair the circuit in time.
3. The definition of insurance is the uncertainty of risk. If the power supply company repairs the line in time, the deceased will not get an electric shock. Then the risk will not happen.
4. Natural disasters exempted from liability should refer to direct losses. The deceased was a tragedy caused by the inaction of the power supply company. Therefore, the principle of proximate cause cannot be used to refuse compensation.
So the insurance company should compensate.
Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.