Tiling work to be complained about?

Thank you for the many statements. I will go through everything tomorrow with a tiler known to us to gain some expert knowledge. After that, I will seek a conversation with our site manager, since the tiler is no longer at the construction site. Our building expert said that he would otherwise address this during the final acceptance. I am just still unsure which is the better way. Whether the site manager is the next contact person, since he is on site these days. Or whether photos to the tiler including a phone call is the right way. Actually, the site manager is the right person for this, isn’t he?

Actually, the construction manager is the right person for that, isn't he?

You can bring up the topic in any conversation – that way the topic will start to circulate. The "wrong person" will reveal themselves; in the end, the boss always counts. Stay friendly, praise the good things and address the bad. Name things clearly, use I-messages and avoid accusatory language. Prepare a path for your counterpart and let them come up with the idea to walk it with you. Be clear about your negotiation goal, otherwise it won't work.

And here are a few more defects found by another tiler who took a look at it.

Water runs to the wall and then pictures of [toilet] and [sink]??

In the shower, this is stupid and should be corrected.

The walk-in shower is arranged so that water could possibly get onto this shelf.

I think the angle should simply slope away from the wall and not towards the wall, or at least be level.
No matter which shelf in the bathroom. Even a shelf at the sink, right?

Strictly speaking, you are right, it is a defect. However, it only becomes a problem in the shower. It would be excessive to have everything tapped off, in my opinion.