If she was legitimately scared, she should've called 911 immediately. 911 will either confirm that it's an officer, or tell you that it's not and send an officer to your location. Once it's confirmed to be an officer, pull over. From her own words, the officer came up to her window and said "what in the hell are you doing? I could arrest you for this.", and she responded to him claiming that she doesn't care who he is and she didn't have to stop. Called his bluff, and he played his hand.
It would've taken the same amount of time, if not more, for her to call 911 and verify he was an actual officer than it did for her to drive less than a mile down the road like she did. People are encouraged all over that if you don't feel safe to drive to a well lit populated area. The department remarked that the officer was in a fully marked patrol car so she should've pulled over. How can she possibly see that when all she can see is flashers behind her at night? Overreaction by the officer no doubt.