The reason why the Busan female officer was involved in a crime scene but even leaked the internal investigation data (and...

It seems like there is a specific case happening right now.
When that female officer in Busan was being completely ignored within the police station, [the person] decided to cause trouble with her, but suddenly thought, "I don't think this person is who she seems to be." It seems they caused trouble that day, went into the police station, found out her name, ran a background check, and uncovered the case.
And then it seems they exposed everything. Because even while causing trouble, they must have clearly thought, "I've made our Police Commissioner appear in the media to issue a public apology."
That female officer probably expected that she wouldn't be able to continue her career in the police force.
So, I assume they either extracted the investigation data or found out through a simple background check.
This is just my speculation.^^