If she can prove he had a history of violence against women, and that “co workers” heard him making threats over the phone before he went home...she MAY have a case. Especially if one of them told the Chief. Or OOD.
The Navy had the authority to prevent him from leaving the base...based on suspicion alone. Whether “the Navy” had sufficient time to react is another matter.
And my experience in the Navy says they would have prevented him from leaving until they were sure he had calmed down...if somebody, anybody in authority had known the above.
I know the Army jumps through hoops to separate couples that are fighting, even without threats of violence. They keep the soldier in barracks until things calm down or are otherwise resolved. I can’t imagine the Navy would be that different. Most now are aware of the dangers of domestic issues.
The Navy could have restricted him to base, but the restriction is not physical restraint, it’s more like a house arrest without a monitor bracelet. It’s more of a “don’t leave the base or else” deal. He would have been free to come and go.