The main reason this case got so much attention is that Mr. Jean was in his own house, not hers. She was not in her house, she was in his house. She was distracted, possibly upset with her paramour, missed all clues that she was not on the right floor of her apartment building nor at the door of her own apartment.
She was an unknown woman at a man's house.
As an aside: it is not good practice for police agencies to allow officers to wear uniforms off duty and in many places, that alone is cause for disciplinary action against the cop. This is a well researched topic and requiring police to leave their uniforms at work (and spend some time re-orienting their headspace) cuts down on violence by cops in their own homes. Domestic violence among police is significantly higher than in other occupations and departments who maintain a policy of "no uniforms outside of work" have lower rates. This includes lower rates of non-lethal domestic violence.
It's interesting that you assumed the opposite, though. But the actual case is far more interesting because of its facts.