What do they feel is the Act of Godwhen refuring to a fire i

We had a fire in our park in a Rv, the fire was the result of a small refigerator put on a table outside the RV in front of a heater vent of which got hot and caused a fire of which resulted in a small explosion of which sent the refrig flying to almost where another Rv was parked. There was a serious amount of damage to the Rv"s on each side. They were told that they needed to contact their insurance because their insurance was not responsible because it was an ACT of GOD. I don't understand. I am not involved but would like you to shed some insite on this for me.