Connecting a keyboard PCB to wires without soldering
I don't want to solder anything, because when I need to take it apart (which I will), that would make it much more challenging.

I think you really, really, really underestimate how annoying and expensive a non-solder connection is going to be.  You can use all the money you save on not buying/making one to buy a few dollars worth of desoldering wick which you can use to clean up the connections when you're done.