If you want the charge line then add it to the MH. It wasn't needed on our CRV.
Prewired does not mean it's compatible with your RV for the lights as sometimes some additional equipment is required, not a big deal.
2009 Holiday Rambler 42' Scepter with ISL 400 Cummins
750 Watts Solar Morningstar MPPT 60 Controller
2014 Grand Cherokee Overland
Bob