I'm not seeing problems with your ZIP. This is rendered with V-Ray viewport IPR. I did have to add a Smooth modifier and set it to Smoothing Group 1, just to get nice smooth normals. TurboSmooth is set to 3 iterations. This is in 3ds Max 2024.2.1, with V-Ray 6.20.02. WIndows 11 Home, NVIDIA GeForce RTX 3080 Ti, 64GB RAM.…
Turbosmooth set to 7 is insane overkill, but ok. I imported the OBJ and reset Smoothing Groups to a single group. I added a Slice modifier to cut away the rest of the model. TurboSmooth at 7. Displace, and loaded your EXR in the OSL Uber Bitmap node. Maybe your import settings need adjustment?