Connecting Concrete Flush Boxes | DALI Circuit

Good day everyone,
I now have to connect the spotlights together. Is it actually possible to switch the spotlights as shown in the first picture?
Or do I have to follow the second scheme..?
The protective conduit would be the Fränkische FFKUS 25. Or if that would not be sufficient, then the 20 one.
As a cable, I would use the NYM 5 x 1.5.

Everything should be switched via DALI.

No matter what, whether it's just picture 1 or 2, DALI can handle it.

What kind of spots are you using there?

Ledvance SPOT ADJUST DALI 8 W 3000 K IP20 WT

Just as an additional question... the shell builder installed the boxes but didn’t wait for me to connect them... concrete was poured... Can I still drill through 25cm of concrete and lay the cable through the ceiling?

Yes, that is also done (intentionally) by us. Installation then on the raw floor of the upper floor.