I have a two gang box with a dimmer switch to recessed lights AND a remote switch to operate a fan/light. There are 3 romex bundles leading into the box, however, only one of the black wires is HOT, one apparently does nothing, and one leads to BOTH the recessed lights AND the fan/light fixtures.
I removed the remote switch a couple years ago when it stopped responding, and do not recall how it was wired previously. Any help here would be appreciated. Happy to further elaborate. For reference, I have a included a picture of a similar two gang box setup, and the specific box with switches removed.