If you can take a Crawshay's, I'd go for it. I'm planning a hunt to Zambia just for the Crawshay's.
But to answer your question, Crawshay's and Grant's/Boehms are two separate sub-species.
The zebra line is a tricky one and people will argue about the differences. They can agree on three species of zebra; Grevy's, Mt. Zebra, and Plains.
They can agree on two sub-species of Mt. Zebra, but the Plains zebra is where it turns into muddy water.
The Grevy is off-limits to hunting.
The Mt Zebra has two sub-species, the Hartmann's and Cape. The Cape is currently not exportable to the USA unless you haul it across the border into Namibia and ship it out as a Hartmann's, which still requires a CITES permit and it would take a DNA sample to tell the difference.
The Plains zebra, the gray area, has five, six, or maybe even seven, subspecies, depending on who you talk to. The most common is the Plains/Burchell's/Damara. Some will argue that the Burchell's and Damara are two separate sub-species? Then there is the Chapman's, the Crawshay's, the Grant's/Boehm, the Selous', the Maneless, and we could toss in the extinct Quagga, which by the way, they are trying to bring back through genetic breeding programs.
And some will read the above and disagree on some or all of that information. It would be nice if there was a biologist somewhere in Africa that would do a comprehensive study on zebra and publish a book dedicated to that work. No other animals, just zebra, chock-full of pictures, DNA studies, distribution maps, etc.
As an example of confusion. I shot a zebra south of Windhoek, Namibia on my trip in 2019. At the time, my PH stated it was a Burchell's. Since then, others have seen the pictures/video and told me, no, that is a Chapman's. To this day, I don't know for sure which one it is.
For me, the zebra is my all-time favorite animal to take with a bow and if I'm lucky enough to return to Africa in the future, a zebra will be on the list should the opportunity present itself.