I personally wouldn't rush with a return. Wait for Meze's reaction first, they probably have an explanation that would calm most people down. I have owned the Empyrean and Elite for years and never had any issues with hair/dust/dead skin inside the cups. They look as clean as on day one, although I keep them on an omega stand when not in use. Perhaps I just shed skin slower than most other audiophiles?
A dynamic diaphragm is very different though, but the mesh might actually provide enough protection or perhaps the 109s diaphragm material is less prone to these things.