On our '06 Dynasty we never operate the "salesman switch", which is a disconnect for much of the 12 volt coach systems. We do, however, open the battery disconnect switch in the battery compartment for both the coach and the chassis batteries when we store our coach for any length of time.
We learned that there are a number of 12 volt systems still powered with even the disconnect switch opened, and some of those systems can take our battery down faster than is acceptable for us. If the "salesman switch" were the only coach battery disconnecting means, I would definitely use it. And if it was giving my trouble, I would find the problem and fix it, so that I could continue to use that load shedding means.
Lots of folks talk about disabling them, but I would personally only do that if I had another means of removing most of the loads from the coach battery when storing the rig for any length of time.
Hopefully troubleshooting the rocker switch and the solenoid(s) that it operates shouldn't be too difficult. I hope it goes well for you.
Jim & Angie, Boise, ID
2006 Monaco Dynasty Countess III
2017 GMC Acadia Denali