That's because the incest patch is a very light touch. It's basically a text file with name definitions provided by the developers themselves for some reason.... let's call it "translation". And has a couple of name definitions "translated" by fans. That's all it is.
How accurate the patch feels depends on how much the devs use it.
In some cases the devs have directly written in names in the game instead of using this file making it feel a bit wonky,
(There's a couple of "Janet's" that feel like they should be "Mom" & one instance where Kaley refers to Janet as "My Mom" instead of "Our Mom").
Issues like this will take a proper mod to fix, this is out of my skillset.
As I've said before, I'm not the original author of the patch. I've just tried my best to keep it updated and as accurate as possible as a fellow user.
Cheers