Here's a start.

Unfortunately, there is no altering, grinding, or topping an exposed aggregrate finish in this case. You would have to cover with something that is inherently capable on it's own, like the paver idea above. But that would cause other issues.

I didn't watch the whole video to hear if it mentions the material they're using. Take a look at TechnoBloc or something similar for both the stairs and walkway. We used TB and really like how it came out.

I like exposed agregate it is interesting whiy not do something like this with of cours the agreagate inbewteeen the slabs to tie the 2 together