Cutting the floor slab due to incorrectly placed drainage pipes

So here is the solution:

The construction company made 2 core drillings into the slab and inserted pipes. They dug a hole from the outside and pushed a pipe under the gravel towards the core drilling. The whole process was done twice. This was for the toilet and the washbasin. For the shower, we are making a side drain; we already gain 40 cm there and for the remaining 30 cm they will remove some concrete without cutting any rebar, and the rest disappears into the 6cm insulation on the floor.

Dug a hole from the outside and drove a pipe under the gravel towards the core drilling.

And hopefully sealed well too...

Where do you mean to seal? Under the slab there are 25 cm of glass foam gravel -> capillary-breaking. The original pipes were also not specially sealed towards the concrete,