IMO it sounds like a matter of convenience for all. Uber picks her up at her door and drops her at daughter’s house. Family member (SIL) drives her home after dark and due to lateness of hour. Maybe a regular occurrence.I asked the same thing earlier, about ubering there and getting a ride home. Someone else commented that is not 'odd'. I wasn't implying it was, but in this particular situation, you have a woman who was taken from her home while bleeding that same night, it begs for an answer.
Me myself, due to mobility/pain issues, sometimes drives, sometimes takes uber or gets a ride, possibly was the case with NG as well, and perfectly understandable. Maybe if she was going to drink, she wanted to take car out of the equation, or maybe understandably doesn't like to drive in the dark. Or, in the worse case scenario, planned to take an uber, but was instead offered a ride home for nefarious reasons.
My son-in-law often schedules Uber for me when I train travel to North Jersey to visit them. It involves a change of trains and if wait time is too long between trains, he gets me a ride . Plus I am often towing heavy luggage. I have never ordered one myself but have ridden Uber frequently.