For those of you who got screwed over by the bug/glitch where Victor will not talk to you and you cannot access the elevator in the Lucky 38, yet you are unwilling to kill Victor, then I have a possible solution for you.

Here is how it worked for me: I went into the 38, stood next to the elevator clicked on it a few times, then clicked on Victor a few times. Like usual I just got the sound effect and no dialog box. I then proceeded to pull up Rex's companion wheel and chose the talk to option. I then scrolled to the bottom of his dialog choices and chose goodbye. As soon as I selected goodbye and the dialog closed, Victor's elevator dialog options popped up. I chose to go to my suite and made it there successfully. After doing this I could once again talk to Victor and use the elevator properly. I even told Rex to stay in my suite and attempted to use the elevator without him and it worked. Next I fast traveled to a far away spot on the map and waited a couple days.(with Rex still in my suite) I came back and Victor still worked normally. Now I do not know if this is a permanent fix, but since I did this I have had no problems with Victor or the elevator.

I don't know if you need any certain conditions, but when I did it Rex was my only companion I had with me, and I had not done his quest yet. Also I do not know if this same trick would work with any of your other companions or not, but you're welcome to try.

I hope this helps some people out.

Yes! thank you! I had the same problem and I tried what you did and it also worked for me! So it appears that all you have to do is tell any of your companions to go back to the lucky 38 casino and victor should talk to you again. I had Boone and Ed - E as my companions.
Thanks again dude!