You can do this particular example easily in Dorico, with no workarounds. The function you mentioned is precisely what to use: Add and Remove Staves as needed. All the other fancy symbols and lines are relatively easy to add, though there is admittedly more functionality needed in this area. And certainly cutaway scores are not really easy to achieve at present.
Here’s a start. It took me about 15 minutes, only because I hadn’t tried some of these functions before. And the font details aren’t very sexy, but you get the idea. I could have spent more time on the custom markings at the beginning, but I just used a big fermata inside two basic glyphs. I also didn’t add the glyphs at the end of the top staff; I couldn’t think of an easy way to create them,
Oh, and I also didn’t really come up with an elegant way of placing the mf inside the hairpin. There might be a function I’m missing. I don’t like how it looks at present.
For the second group of staves, I would use a separate flow and add that as a new music frame on the page.