4.5 cm too little boundary distance - garden wall

3cm? Even the five centimeters were ridiculous, but this is now the ultimate nonsense... Man man man

By straightening the boundary marker

What kind of boundary marker is that now? Show a picture.
Who straightened it?
Who says it’s in the right place?

The gardener is coming in a week.

What was he basing that on?

I hope we can reach an agreement.

If you’ve already agreed on 3cm, then no further agreement is needed. Next week at the appointment, fire up the grill, have a beer, and play a round of skat. Everything else is a waste of time.
Of course, you can have a surveyor come. The fees for the cadastral documents already cost 10m² of farmland. Boundary notification another 60m², boundary restoration another 60m². Then lawyer 100m², mediation 80m², ... and everyone loses three years of their life ... except the surveyor and lawyer, who win.

So if he doesn’t give up the 3cm, I would just wait it out. I seriously doubt that you would then be ordered by the court to restore it. That is completely disproportionate.