If she was not in car at drive-thru, I think LE would be more likely to say they believe foul play occurred, than they do not know. That is, if the video exists and it is clear.
I think NG focused on the other workplace instead of BK because she likes to present the person as young and naive as possible, i.e every high school is a "cheerleader" etc...she probably did not want to say she worked in a place similar to Hooters, for whatever reason. But if Heather no longer worked there, it is just plain bad info,and I am not surprised, she often gives bad info. JMO