Thanks, Eskarn! I didn't change the closed0 or closed1 values yet, might adjust that later to allow the player to get into the office at other times of day if need be. I also didn't change the city_pos value as I wasn't sure what xyz coords I should to change it to.
I set "locked = true" to "false" in office0.dat, though I'm not 100% certain what that did.
I also changed the code as you recommended in run6_state.dat and now when you try to go to the office it does exactly what I wanted--you immediately load in the entry room of floor 16 as though you've just exited the elevator. Interestingly, these changes moved the Office icon on the city map to a different position, and the icon now reads as Office16. I'm not concerned with those oddities though, they can persist for all I care.

I'm trying to slowly convert the Tentacle Dreams story into something of a hybrid between the story and dungeon. I've already incorporated some of the adjustments made in the Tentacle Dreams Ex mod someone converted from 3.0 (like the ability to touch and play with the girls before you're normally able to, and bringing in some of the sex toys to Saiko's room and the office).
Next step is going to be figuring out a way to halt the story progress but make the girls seem more active. Eventually I want to make the girls "sandbox" around their rooms in simple ways, sort of like how Monica moves around her office while you're working on her computer. I'll have Monica sit at her desk for a while, then get up and move to the sofa to lie down for a nap, then wake back up and go back to sit at her computer again. Meanwhile the player will be able to play with her in each position she puts herself into. I've already started incorporated some code from a different thread explaining how to put the girls into a limp pose (rift's code, i think), right now when Monica sits on the sofa as she waits for you to fix her computer, you can pose her a bit. I'm a ways off from where I want that to be, though.. she still reverts back to her initial pose when I really want her to go into a pure ragdoll/limp pose. Baby steps, I'll figure it out eventually.

I'm hoping that eventually I'll figure out a way to move the girls around depending on the time of day. I could have Saiko work at the office (in the windowed cubicle computer room maybe), and then maybe at night Monica goes and visits Saiko in her apartment. That sort of thing.
I'll be removing most of the story entirely, if I can, and it'll be more like a dungeon experience except the girls will be just sort of living their daily lives while the player gets to enjoy them in various ways. It's probably beyond my capabilities but I want to try to incorporate some of the great Dungeon Ex features also. I'm a long way off from that though. I also need to figure out how to get the girls to accept commands like in the dungeon. (Example: "monica open mouth" - currently if you tell her this in the office she just continues to repeat her scripted lines about either telling you to fix her computer, or telling you to go home)
This is all pretty early in the process and I'm pretty new to modding/coding, so I'll probably have a bunch of questions over the next few weeks. Apologies in advance, and hopefully this will actually lead to something worth sharing with the rest of XSP players.