Are you sure about that? They say "full 3D shape geometry, texture, and layout" which doesn't preclude it being a splat but maybe they just use splats for visualization?
On their paper they mentioned using an "latent 3D grid" internally, which can be converted to mesh/gs using a decoder. The spatial layout of the points shown in the demo doesn’t resemble a Gaussian splat either
The linked article of the grandparent says "mesh or splats" a bunch, and as you said their examples wouldn't work if it were splats. I feel they are clearly illustrating it's ability to export meshes.