At Terry's ATM and on the computer address search, her last name appears as Munroe. When her son Josh signs in to use the Virtual Reality gear with his friend, he signs as Munroe. On her son's computer info, his name is spelled as Monroe which is what the credits show, recently as December 2020.
In one of the early scenes, we see Karen (mother) traveling along the street in her Volvo sedan from a distance, in which you can clearly see there is no-one visible in the passenger front seat. It is empty. In the next scene we see her son sitting in the seat.
When trying to kill Elliott in the test car, the killer causes a mechanical switch to flip. These cannot be engaged by electrical controls.