Glb rendering artifacts within Cesium viewer - others fine

I’m creating my own tileset and encountered some odd rendering behaviour with a few tiles.

Not certain if I am missing anything, I decided to check a few other programs:

Babylonjs:

Threejs:

Cesium viewer within VSCode gltf Tools preview

Khronos gltf validator reports no issues. I only started getting this issue when I decided to merge objects by colour.

See the attached offending file:
16x_-16_0_16_G0.10.glb (3.6 MB)

There’s a handful of them within my tileset.

CesiumJS: https://cesium.com/downloads/cesiumjs/releases/1.90/Build/Cesium/Cesium.js
Browser: Chrome