I have a FileSixty keyboard for sale for £16 plus p&p (UK preferable due to the pain that it now is sending stuff abroad). I have given this a gentle wipe over and pressed all of the keys on a zeddy and all worked. I believe strong double sided tape may be the way forward to stick this on. This also...
That could work. You could do it as a survival horror where you just need to escape or a ‘who dunnit’ where you need to figure who is the Thing in order to win. Or doubtless many other options.