The ground rod should be flush or below the surface.
That’s what I used to tell our local code enforcement inspectors using the argument that you need the entire 8’ in the ground, not to mention that it is hard on lawn mowers!.. but they all want to see the connection. I’ve since started digging around it to expose it for the inspection, then bury it back after the inspector leaves. Use a connector that doesn’t rust if you do that.
Your inspectors need to read the book.
The clamp needs to be rated for direct burial.