Who is allowed to give the order?
Basically, it is the owner of the property and all authorized persons. In the case of a developer, that means the company (because it is the owner) and the employees appointed by it (you never know which employees have which authority).
If the house connections were within the scope of services of the developer, you’re off the hook (as a customer you don’t even have the authority to tell anyone anything there). The delay, the extra effort due to the erection of a new scaffold, re-digging, default interest (construction time guarantee), etc. are all at the expense of the builder.
With a construction company, on the other hand, it’s a slightly different matter. Usually, you commission the supplier yourself.
However, the civil engineer should not have dug at all. He immediately sees that the scaffold cannot stand as it is and should have withdrawn again. Overall, as a customer/building owner, you are somewhat taken for a ride now, but cost-wise nothing should actually come your way.