Babylon.js billboardMode in MapLibre Custom Layer

[albertoscandolara]

I'm integrating Babylon.js with MapLibre by adding a custom layer for rendering 3D meshes.

Following the documentation example,
I only added this line in the onAdd method, after rootMesh2.position.z = 25;
[rootMesh, rootMesh2].forEach(mesh => mesh.billboardMode = BABYLON.Mesh.BILLBOARDMODE_ALL);
This was intended to enable billboardMode for my meshes, expecting them to always face the camera, similar to how it works in pure Babylon.js. However, the meshes remain static and never face the camera.

Am I missing any additional properties or setup required for billboardMode to work correctly in this setup?
Could the issue be related to how the camera matrix is being frozen or updated in the render function?
Any guidance or suggestions would be greatly appreciated. Thank you!