NY fashion week is held in February and September. People in the crowd were long wearing coats, so it must have been a colder September or an exceptionally mild day in February. Either way, the couple in the intro would have been very cold jumping into the fountain.
Lainie draws an exact three dimensional representation of the murder weapon based on a two dimensional entry wound which is absolutely impossible.
Lainie says she found traces of glass in a wound which is impossible since skin is too soft to scrape off glass, and since the award did not break in her back there would be no glass from that.
The tip of the glass award was broken off in the apartment in the struggle prior to the stabbing so it would not be present to make the clean entry into the victim as described. In fact, it is highly unlikely the blunt tip would be able to penetrate the skin to make a stab wound.