Fun With Pestilence Elevator bug?

I've encountered a bug in the Fun With Pestilence quest in which the elevator at the Empire Arms Hotel will only take me to the 6th floor even when I clearly hit the 5 button. What can I do? It's driving me crazy and idk what to do at this point. I can't noclip as the 5th floor is a completely seperate cell. I'm playing on Steam if that helps.