When the female doctor gives the time of death for Laurel, she only says 11:59 without saying PM. Regardless, when giving time of death it's given in 24h time, which would put Laurel's death as 23:59.
After the doctor pronounces Laurel dead, and it shows the clock, the second hand is not moving.
Obvious stunt doubles used for Thea and Laurel during the fight in the bunker with the League of Assassins.
During an attempted resuscitation, medical staff deliver cardiac stimulation via a defibrillator. They apply conductive patches as is standard practice but they do so on top of the patient's hospital gown, which would interfere with the delivery of the electrical current and may melt or catch fire as a result.
In a scene where a patient in hospital goes into cardiac arrest, the medical staff is seen working on a resuscitation for barely 60 seconds before declaring the patient deceased. That amount of time is far too short to give up on resuscitation.