Over-allocation in reallocation

is the owner the king

Not when it comes to land readjustment.

Just as little as you can be forced to sell

It is not that complicated in the readjustment process. Of course, efforts are made to reach an amicable agreement. That is why negotiations take place. But a single uncooperative participant in the readjustment cannot prevent the procedure.

the established rules are more the municipality’s wishful thinking

The rules are set out in the fourth part of the Building Code.

And therefore there must be two transactions

No. Readjustment works differently. You contribute your property and the municipality decides whether to redistribute according to values or area. Is there even a legally binding development plan yet? If not, we are still in the municipality’s exploratory phase, which, given already apparent resistance, would probably not pursue any further planning there and thus the property would never become building land.