Oh, wow. Then, I would really think those caps would fit on the Das. Have you tried the caps you ordered for your company on the Das?
Unfortunatelly all G80s use UK layout thus I was not able to test BS, Enter and a few others. Besides this issue, letter keycaps fit just fine.
Don't blame me for UK layout, I do hate it. When ordered them I was not able to find any black US Cherries stocked in Europe.
Back then, I used keycapsdirect services to order custom keycaps (English / Greek) for these Cherries.
Seriously. No, seriously. You could sell them here, for sure, if they fit the Filco, Das, iOne, and G80's.
I wish I had time turn this into a business but I'm already busy enough.