Neighbors tree caused damage - no coverage due to act of God?

[CJ M.]

So the neighbor directly across the street from me, had a big chunk of a tree break off during a storm and fall across the power lines and road (and into my tenant's yard). When the tree hit the power lines, it pulled a metal post out of the roof of my rental, as well as the shingles around it. The owner's insurance company, called me and said they won't cover the damage because it was an act of God. To anyone on here with insurance as a background, does this sound correct? Thanks in advance.