Resistors are still used in a keyboard matrix as it allows NKRO on a hardware level. So they aren't just for LEDs.
Nope. I'm pretty sure this was just a typo and you meant to say "diodes". Anyway, great posts and that should get the OP's board up and running again.
Just to note: Diodes have polarity and need to be installed the correct way round in order to work (the stripe or line is always closest to the minus side / cathode), so just make sure to install it the same round as the original was. If it's off the board already and you can't remember which way it was, the ones for the other switches in similar positions should be the same way round so you can use them as a reference. Resistors can be installed either way round.