I was responsible for the rolling smoke.

In order to get started with the smoke simulation I imported all of the geometry from an alembic cache and deleted all unnecessary collision geometry for the simulation. This was in-order to save on overhead and simulation time. After all the need geometry was grouped together it was turned into a rigid body collision object and was set to use the geometry collision instead of volume based collision. This was done because the required division size to get some of the geometry to appear was too small for the scale of the simulation. After all this was set up a box was added to be the emitter for the pyro simulation and the pyro simulation was created. After that I fine tuned the simulation to be the right speed and density for the shot. RGB lighting was then set up and it was rendered in mantra with the collision geometry acting as a matte. It was then comped in the shot using the RGB lighting pass.