Okay, stopped by the dealer and he says in his 26 years nobody has asked for this. I don't see how this could be so difficult. He warned about getting stuck in the sleeping area if power goes. But I can climb through the sink area, just not practical. The need is only too open enough to get to the bed and close for nap.
The other option would be to put a hatch door in the slide wall. Not much better than climbing through the sink area.
I see posts for adding a second switch for the pump, I assume it would similar but with a different type of switch.