Multi-branch connection is a bit low

Good evening everyone,

after our screed installer was finished, our architect came to us and said that the upper edge of the multi-socket connection is about 8 cm below the upper edge of the finished floor, and therefore we would not get a clean edge. However, there is an extension system from Fa. Hauff for about 400€ to bridge the remaining 8 cm.
My question to the group of experts here:
Is an extension to the upper edge of the finished floor really necessary? Otherwise, will we have problems when the supply connections come?
Please share your experiences. We would like to save the money if possible.

Thanks and regards

after our screed layer installer was finished, our architect came to us and said that the top edge of the multi-trench connection is about 8 cm below the top edge of the finished floor,

Funny: elsewhere here we are just dealing with spelling, and there I classified it as subordinate. Here you can see a nice counterexample, which comes in handy, thank you: the multi-trench connection has precisely the purpose of not using the trench (or excavator) individually for each trench

The second unhelpful answer:

For the "somewhat" too low height, I expected 1-2 cm. 8 cm is a gross deviation. Was your installer of the [Mehrsparten-Hauseinführung] aware of your upper edge of the finished floor? Then I see the fault with him. Request a correction.

Yes, it is necessary, the multi-utility house entry usually consists of the raw component that disappears into the slab and the installation part. The latter will not fit as is.

I expected 1-2 cm for the "somewhat" too low height. 8 cm is a major deviation. Was the installer of the multi-utility house entry aware of your finished floor level? Then I see the mistake with him. Request rectification.

I rather see the mistake with the civil engineers. They installed the multi-utility connection. Then came the floor slab, floor insulation, and then the screed. And now we are missing about 8 cm there. Is there a regulation that states that the multi-utility connection must be flush with the finished floor level?

The installation manual