Thanks for the replies, but I would like to keep the triangulation created by the surveyor. When I create a surface from points, a new triangulation is created that does not adhere to the break lines added by the surveyor.
An alternative might be to add the triangles as break lines to the surface created from points, but from this post - TinSurface from 3D Faces - Civil3D - Dynamo (dynamobim.com) it seems like this will make the script heavy… but if that is the only way… then that is the way I will follow.