Calculating the scope of earthworks - Who is responsible for it?

We are currently looking for an earthworks/civil engineering company and have received two different statements regarding this. The house builder (prefabricated house manufacturer) says that the earthworks/civil engineering company must calculate the measurements, meters, m², and m³ themselves from the sections, construction documents, and soil survey. The earthworks company says it is customary for the house builder to provide the information.

Who do you think is responsible for this?

A civil engineer who has any regard for himself will only accept his own calculations/planning based on survey documents, foundation recommendations from the geotechnical report, and construction plans.

Any civil engineer who wants something like that from the construction company either has no clue or too many orders.

A civil engineer who values himself will only accept his own calculation/planning based on surveying documents, foundation recommendations from the geotechnical report, and construction plans.

Any civil engineer who wants something like that from the construction company either has no clue or has too many orders.

Thanks. :-) These are exactly the difficulties I hoped to handle with a prefab house. That everyone says something different and I, as a layperson, am at their mercy. Let's see if we can find someone to take on the earthworks/civil engineering works.

Was also done by the civil engineer with us as well