It does not lok like the 'Borissii' i once grew. I had it from Sündemann so it should have been right. That had broader leaves
None of the pictures of the Borissi complex in "Horny" has these acute leave apices.
It is easy to say "Porophyllum = Kabshia" and to say what it is not.
To say what it is is more difficult especially since there must be so many unnamed hybrids out there.
Perhaps some more pictuers also from the side would be helpful
Göte