Close up pictures would help. I don't know that I've ever seen someone wear out a cherry mx switch in a few years so yes, it's probably the PCB.
Or, Maybe you spilled something in it? Maybe the contact in switches are gummed up? I'm sure there are a few people around here with spare switches, but we need to know which switches you have.
The filco case is compatible with the phantom PCB, but that might be beyond your soldering ability.
We need some more details for better feedback.