Teardowns I've Worked On
In a sense it does, but not the same way the patent describes. Really, the size of the plug is limited by the 3.5mm connector, not the connectors. If you want more info, see the headphone jack teardown.
Based on my measurements on my own device, the diameter of the control pad is pretty much dead on 2.5cm.
Towards the bottom right, there appears to be a small tab to help keep the back attached. The black goop I'm assuming is glue or a seal of sorts. And the grey-ish blob towards the top right looks like foam with probably a metal mesh surrounding it. I'm not sure what the technical name is, but that type of foam is common in electronics.