It seems to me to be logical to conclude that Steven went to Las Vegas, since the day before he was captured by the Video, he said he'd not be able to attend a church function because he'd be in Vegas.
That all happened on the same day: Dec 13th, between 7:57am and 12:00pm, Pacific Standard Time.
It's broken down practically minute-by-minute on our timeline page. Have you had a chance to review it?
Now, he ends up in Henderson, parks the car there in this neighborhood, yet the following day the Voice mail is check from Las Vegas?
The call to voice mail hit a tower in the "Las Vegas area". Henderson is a suburb of Las Vegas and is part of the "Las Vegas area".
If this is so, it "seems" logical to conclude that he rode with someone else to Las Vegas and he himself checked his voice mail messages that morning.
Still wondering of course just musing here.
Not sure if it's so; perhaps you can explain your theory a bit more?