Neighbor shot a shotgun through the wall into my teanants bath

[Ryan Thomas]

My tenant called me today to let me know her neighbor shot a shotgun through the wall into the bathroom (this is a condo. I haven't had a chance to go by yet but it seems like the only damage is to the walls, but at the same time if my tenant had been sitting on the toilet, she would have most likely been killed. From what I understand, the next door neighbor keeps a loaded shotgun and a 16 year old was visiting nextdoor and accidentally shot it in the middle of the night (most likely a bs story).  Ive also recent learned there are 7 people living there and they are "sketchy" according to my tenant.

My tenant doesn't want to press charges. Does anyone have advice what I should do? 

How to approach the owner next door about evicting these tenants?

Does the damage go through the next door neighbors insurance?

Is there any advantage to me pressing charges? Disadvantages would be wasting my time in court, etc.)