The MiniCommand can (in theory) be used with any MIDI device, as its operating system is open source. As long as you can write code, you can tailor its function to your needs. (It can be used with the MnM for example, R&W have created firmwares for this.)
I don't code, but are you familiar with the Arduino environment? I can try to find a few links for you if you haven't explored the R&W site yet.
I have no idea how easy t would be to incorporate the MC into the Shruthi/Sammich setup you describe, but you might try emailing Manuel at R&W. He's usually pretty busy but he might be able to help.
By the way, that's a great setup with your 2 Shruthis, hope you'll post some music made with it soon