You may be right about the cook, but I think he could have been outside having a smoke, or bringing out the trash, and could have been walking back in at the same time he saw her walking to the car. He may have thought it was just someone she knew, and thought nothing more about it and went back inside of the building. I think if he was involved, he would have never said a thing about anything. That drew the attention towards him with LE asking questions. The only reason I think he would have said something, would be if he was involved directly and wanted to divert attention away from him, and towards someone in a dark car, but that means she would have had to hang around til he was done working, (if cooks are the last to leave) and left with him. She would have been seen waiting. Just my thoughts.