I’ve ran into the same problem with photogrammetry models exported as Cesium tiles from Agisoft Metashape (as well as Reality Capture): https://community.cesium.com/t/line-trace-passing-through-cesium3dtileset-on-high-lod
Unfortunately I haven’t found a solution yet, much less the exact reason why and where this problem is caused. I’m not sure whether it’s the modelling or in my case photogrammetry software, the Cesium tiles format itself, Unreal Engine, or the Cesium for Unreal plugin.