Can't find companion in instructed to go to Lucky 38!!?

In Fallout New Vegas, I instructed Veronica while at the Mojave Outpost to return to the Lucky 38 so I could recruit Cass to complete a Van Graff quest. When I returned to the Lucky 38 to retrieve her, she was no where to be found. I've already checked where I picked up Veronica, and even waited for a while. Is there a solution to this?!