Rex has dissapeared many times in my playthroughs of New Vegas, but I've always simply been able to reload an auto-save and find him oncemore. Now I can't.

I had Rex and Cass with me when I arrived at Happy Trails Caravan, having high hopes that I could bring my companions along. When I learned I could not, I sent them both back to the Lucky 38 and went about my business. However, after returning from Zion and completing Honest Hearts, Rex is not in my suite. Has anyone else encountered this problem? Is he gone for good?

Try going to Freeside and to where all the kings hang out thats where i found him on my playthrough