The facts are that the police were roaring up and down the street right in front of the TT. Postal knew the president had been assassinated a short distance away. I believe the distance from the TT to Dealey Plaza only is about three miles. Regardless, she didn't have to know that the man was the "killer of JFK." What she could see with her own eyes was the that the police were looking for someone on her street. Brewer tells her about the man. It doesn't take Nostradamus to conclude that someone entering the theatre without buying a ticket is acting suspiciously - particularly when Brewer is following the guy - and so she reports that to the police having no idea whether this is the guy they are looking for. Maybe he is and maybe he is not. All she knows is that the police are looking for someone in her vicinity and it has been brought to her attention that a person in her theatre is behaving suspiciously. She reports it and the police respond accordingly. All Oswald has to do is clear this up by explaining himself instead of punching a cop and pulling a gun. Your hero can't do that, however, because it turns out he is the cop killer and assassin. There is absolutely nothing here that is unclear or suspicious. It is a logical sequence of events.
All these words, but NO supporting evidence. No surprise there. Your main problem is -- she NEVER saw the man claimed to be LHO, therefore, she had NO way of knowing how he was acting.
Tell me why she thought a man that she never saw was a suspect in the killing of JFK when DP was miles away. Go ahead.