Curbside pickup at baggage claim is not allowed at any terminal in Las Vegas. All picker-uppers are directed to drive into the parking garage and park in the short term area. The first 15 minutes are free, so if all the timing works out just right there is no charge. Or (again, if the timing is right) the driver can pick someone up curbside in the parking garage at the designated passenger pickup location.

Source: https://www.mccarran.com/Park/PassengerPickUp.aspx

Last time I picked someone up at LAS T3 I drove around the airport like 6 times looking for baggage claim. It turns out the traffic signs say "Taxi and Limo Entrance" or something like that. I didn't drive in, so I can't tell you if you get a ticket for it. Heheh.

IMHO the best use of time and energy is for her to arrive early, park in short term parking, and wander around the parking garage until someone with a Smart Cart full of luggage comes out and unloads it into their car and drives away. Then she can take the cart and meet you at baggage claim. Yep, you pay for parking, but you don't have to pay $5 for the cart, so it balances out.