Damo and Nathan teach different facets/approaches to internal work.
Damo's approach is primarily physical and movements. Everyone should do some body maintenance anyway.
Nathan teaches sitting meditations as taught by Wang Liping in the Dragon Gates framework. Sometimes Nathan might teach some LHBF or taiji, but that would be something incidental and not mainstream for him.
Damo and Nathan are not mutually exclusive, and I had a period of time when I studied with both of them.