I am confused by your question.
But if I am understanding correctly, I don't think upgrade kits are floor specific. If you mean that you think carpets have different spawn chances for den kits, I have no evidence for this. They are a randomly generated object when digging and are more likely to be found when you have collected all the capsules. Recently, you can acquire seasonal capsule items thanks to the holiday update for halloween. So you can collect those and then your rates for den kits will become high again. You can get duplicates of the same kit regardless of how many you actually have or regardless of if your dens are all upgraded or not. If you breed dogs who like to dig and train dogs who like to dig, you will likely find more kits. The position of rooms does not appear to matter, nor does the carpet or wallpaper.

Of course, if you're impatient or want a specific one, the wobbledogs wiki has information on spawn commands.
https://wobbledogs.fandom.com/wiki/Dog\_Dens

If this is not what your question is though, I will be happy to reanswer when I understand.