Incompetent writer, or an incompetent writer trying to be politically correct?
More likely that the writer didn’t know the name/gender of the officer who tracked her down.
In that case, I know that you know the convention has been to use the pronoun “his” when the sex is unknown but the number is known singular. Of course, one could say “his or her” but that’s cumbersome. Both are more correct than “their.”
True, though I have no idea what the AP style guide (assuming that’s what they follow?) says on the topic.