How often do you see this kind of connector problem on X10 units in your shop? There are less and less of them in the field, but the connectors are getting older and older.
How often does a lifted ground cause an alternate return path to destroy a few components on the board (I noted that you pointed out some possible problem components on the board when you started)? I would think the problem would be the remote sense wire (not the ground) if that happened. Or was that what you were suggesting?