The lab
Story elements usually need some time to mature.
This makes it likely that the lab story will run longer release cycles than the lab girls.
The lab girls
It is therefore likely that the "lab girls" will be more active than the lab itself.
Which is to say that the ladies will venture outside of it, as we are seeing Sara do.
So as for seeing the girls around? Quite good chances of that.
They also fit the long term trend of the game, which is the specials.
The specials
This trend was originally was due to cost-factor (specials are more content-effective than regulars) but due to their ability to introduce new girls, they are more than just cheaper/more effective by now.
They are born with a large number of improvements this far into the project.
To name but a few,
- High maturity (Learnings from prior years)
- Flexible (Ex. MnM and Sara)
- Purpose made with background, traits and for specific tasks/jobs (makes creative effort easier, a huge plus)
- Can do what they want without another girl needing the same.
And of course, they are chosen directly by Darkhound.
I reckon the lab girls (and others) will be around and do fine
Note
All imo and guesswork, and while based on broad historical trends may or may not predict the future accurately for said ladies and location. Whatever Darkhound choses will go.