Passenger pickup at McCarren Airport with class A motorhome

Parking will certainly be a problem at the terminal...but to just swing in and pick-up someone can be done at "Arrivals."
Full size buses from city transit and from the big hotels do it all day long.

You will have to park and wait off site somewhere on a side street and use your cell phone to have your passenger call you when they are out front....then you can swing in and make the pick-up on the fly.