Okay, good to know more about the situation! It's much harder to give the right "spin" on things when we don't know who we are speaking to and can't look at what we each point to when speaking! Fully understand it being difficult to get the details when switching who does what! I hope I never have to take over cooking! I sure would miss my biscuits!
The third switch from left on top row, should possibly be labeled "compartment lights"?
Do the switches have labels that you can still read? They tend to rub off!
Sounds like you may be using a cell phone to look at the postings, so it does get super hard to read details on drawings.
But I now have the time to do as much indepth looking as we need to get things cleared!
But the idea should be that the top row RIGHT hand side is compartment lights. Then the bottom row LEFT end is the cutoff for the coach battery. Next to it in the center of bottom row is the chassis or start battery cutoff.
So you have three different groups of electrical stuff in the motorhome.
One is the chassis and powers the things we would find on most any truck.
Headlights, horn, wipers, etc.
Second is the coach and gets charged from the cord plugged in. It powers the smaller stuff added to make it an RV that run on 12Volt battery power.
Inside lights, water pump, fans, and an important one is the controls on things like the furnace and air conditioner!
Third is the 110AC that we get when we plug in or run the generator! That powers the main motors on the air cond., microwave, normal Ac(house type?) outlets where plug hair driers. One of the big things this AC powers is the converter(charger?) that charges the batteries.
These connect together at times and not at other times, so it is often really confusing to get straight!
Like the cord? It seems to power the inside lights when we plug in but then if we unplug, they stay on, so it is the batteries that power the lights! Right! but if we unplug and the batteries run down, we still go dark!
Best of luck and keep asking questions if it is needed. Very few of us were born knowing anything about an RV, so we've all been there and been confused.
I bet you are a better cook than me so I'm willing to swap if we get in a pinch!