I dismissed Veronica to the Lucky 38, I recruited Raul and sent him to the lucky 38. I went back to the Lucky 38, re-recruited Raul and eventually dismissed him to his shack. I then returned to the lucky 38 to find that Veronica was nowhere to be found. I checked the 188 but wasn't there either

I had the same problem (Rex and Veronica disappeared when I sent 'em to Lucky 38), but this was before the patch. I'm still on the way to the strip in my new post-patch game, then I can't tell if this happens even with patched games.