[echelon]

Your link above (Splatter Image) is not the same code / paper / research as Bolt3D.

This is a previous paper/work by the lead author a year before they interned at Google Research and produced Bolt3D.

Bolt3D appears to be his intern research project done in conjunction with a bunch of other Google and DeepMind researchers.

I don't suspect there will ever be publicly available code for this.