It would be helpful to see a picture of one with a Gemini mounted.
There are such pictures over at the indiegogo page. Since hotlinking images there seems to work, here are the other three:
[img]https://c1.iggcdn.com/indiegogo-media-prod-cld/image/upload/c_limit,w_695/v1552927596/lcig2mamg8zeomzmhl9n.jpg\" border=\"0\" class=\"linked-image\" /]
[img]https://c1.iggcdn.com/indiegogo-media-prod-cld/image/upload/c_limit,w_695/v1552927719/g57mubddrjga4ljemv3a.jpg\" border=\"0\" class=\"linked-image\" /]
[img]https://c1.iggcdn.com/indiegogo-media-prod-cld/image/upload/c_limit,w_695/v1552927658/charsggcv5qcupm7ladg.jpg\" border=\"0\" class=\"linked-image\" /]
"The car mount kit allows for charging whilst the Gemini PDA device is mounted."
When comparing the two images of a Gemini in the clamp, I notice that on the top image, the front of the clamp is more or less flush with the front of the Gemini keyboard, while on the second picture, the rear of the clamp is more or less flush with the rear of the keyboard. If I've guesstimated correctly that the clamp overlaps the keyboard slightly, such that the lid would hit the clamp rather than be able to slam shut, it might be possible to slide the Gemini far enough forward in the clamp, that the rear of the clamp is in contact with the edges of the screen, even when it's fully open, but that's obviously just my guesswork and conjecture.
It seems (to me) that nothing is
designed to hold on to the lid. Given that the Gemini has a fixed opening angle, it should be possible to design a clamp such that it holds on to both the sides of the keyboard AND the sides of the screen. I'd guess the answer might be that this clamp, to keep cost down, is partially based on some standard design, say a small tablet clamp, and that a more advanced design would make it too expensive, but again, I'm just guessing here.