I killed all of the legion in the fort including ceasar and his guards, then went and untied benny and let him go. We ran from ceasars tent together but I couldn't find him after we passed through the gate. I assumed he fast traveled somewhere but could not find him at the tops or lucky 38. Has anyone else done this and know's where he went?

I believe the old rascal has done flown the coop. Don't think you'll ever see him again, frankly. Pretty sure once you help him escape, he disappears permanent like. He knows House or his ex-henchmen would be obliged to do him in if he returned to the strip, so he thought it a good idea to head for parts unknown.

Correct as soon as he leaves the fort he does one never to be seen again.

Shouldn't of freed him, he's a snake.

Cheers