fragment rendering errors for PrefabBufferGeometry + PhongAnimationMaterial

[clindsey]

I'm not able to get PrefabBufferGeometry instances with PhongAnimationMaterial to render correctly when they're overlapping on the screen. It seems like the fragment shader isn't able to correctly depth sort. I'm updating transformed in the vertex shader to position the object but the fragment shader isn't picking up on it. Is there a way to correct this, or should I just stick to ToonAnimationMaterial like in the examples?

example code - https://codepen.io/clindsey/pen/ydeaKx