I think I may have mentioned it in the video.
The assumption on our part, is that BMW supplied the proper wire size to that additional lug to supply the items they have run from it. We didn’t think they would have planned up to a 25a draw on the 2 channel amp, or a 40a draw with the 4 channel (I doubt either would pull close to that real world)
Long story short, we prefer to leave as many things as BMW intended, and have ours operate as independently as possible.