I have a DIY idea, that might be easier than trying to figure out the conductive printable formable plastic part.
Basically a spring loaded normally closed group of buttons all connected to a ground plane through the springs. They make contact with a pcb flipped copper down forced closed by the springs. A small nub sticking through a via in the pcb is able to be pressed to open that switch.
I'll see if I can work up a drawing to better explain this, tools are limited here at work.