If Selma can hear Eve sneaking up and even detect what kind of perfume she is wearing, from outside a room, then why can't she hear Eve pick up's Darien's PPT and warn him?
If Sahmbi really wanted to completely get Darien out of his way, why didn't he just send Darien back to the future? He already knows a second trip may kill Darien.
The police officer was nowhere in sight and drove fast just to catch up to where the car Darien and Eve were in. How in the world did he know they went over the embankment? Let alone the precise spot.