I believe I have determined why you no longer see colleagues at the office anymore: They're just not going. There's a problem with the work_office.lpai file (and presumably several other AI files) in which a condition for them actually going to work is failing. I have tested the various conditions and functions used in the script, and the only one that's failing is the condition on line 7 based on DayOfWeek:
DayOfWeek >= 2 && DayOfWeek <= 6
I've made an action/scene to test the various aspects of the AI script, and it also prints out the value of DayOfWeek, and it appears that DayOfWeek is set to -1, regardless of what day it is, so the condition will never be true, and thus people working at offices and a few other places will never go to work. Assuming you have an office job in your game and have met some colleagues there, it's easy enough to test this by just removing that condition from work_office.lpai, so that line 7 changes from:
If WHEN > 8 && WHEN < 19 && DayOfWeek >= 2 && DayOfWeek <= 6
to:
If WHEN > 8 && WHEN < 19
Doing so will then make your boss/colleagues start appearing at work again. The obvious downside of this is that people working the jobs relevant to that script will then go to work every day instead of just 5 days a week.
DayOfWeek is used in several AI scripts, so it seems like there's a lot more that's broken beyond just people not going to work at the office.
I've also attached the test mod I used for reference