Yes, it is true
I didn't know of that particular board before, thanks for the idea! I think it is the best solution especially for you, since you need to drive more than one motor. The one of the gears is a very annoying issue to deal with. I was lucky enough to have access to a 3D printer, so I printed exactly what I needed. Otherwise you should think of driving belts or of some other ways of transmitting power to the knob. Concerning the Nunchuck, if I were you I would use its joystick to control the mount, and its two buttons for the focus,. Alternatively you could for example think of solutions like: if I press one of the nunchuck button, the joystick becomes the controller for the focuser instead of the mount. Then, if you want, upload your project once it will be finished!
Nunchuck Controlled Telescope Focuser