normal estimation of mesh open3d c++ - c++

Question

I have a problem when re-computing my surface normals of a mesh in open3d. The problem is that the estimation is not good enough and I don't know how to make it better. From the image below it cannot be seen that the mesh has a hole in the middle of the belly.
However, if the same mesh is seen from the side it clearly has a hole.
If I then use MeshLab to do the normal estimation the hole can suddenly clearly be seen. MeshLab support 4 different functions for the normal estimation of a mesh but the result are more or less the same no matter which function I use.
Here is the same mesh after estimating normals with MeshLab.
I find it very strange that open3d does no even come close to the accuracy of MeshLabs normal estimation, and I believe that it is most likely because I miss some important calculation before using open3d normal estimation function.
Here is the code which is use for the normal estimation in open3d:
void ReconstructionSystem::constructMeshDeformation(glm::vec3& intersectionPosition, glm::vec3& robotPosition) {
double depthOfProbe = glm::distance(intersectionPosition.z, robotPosition.z);
double affectedArea = 0.015 * (depthOfProbe*100.0); // 0.015 is a random value the function simply works good with it
if (affectedArea > 0.08) {
affectedArea = 0.08;
}
deformatedMesh = std::make_shared<open3d::geometry::TriangleMesh>(*final_mesh);
int i = 0;
for each (Eigen::Vector3d vertex in deformatedMesh->vertices_) {
glm::vec3 vex = glm::vec3(vertex.x(), vertex.y(), vertex.z());
double dist = glm::distance(vex, intersectionPosition);
if (dist < affectedArea) {
double ratio = dist / affectedArea;
double deformationAmount = glm::cos((2.0 * M_PI * ratio) / 4.0);
deformatedMesh->vertices_.at(i).z() -= depthOfProbe * deformationAmount;
}
i++;
}
*deformatedMesh = deformatedMesh->ComputeVertexNormals();
}