If you have the Renogy charger on hand or on the way, I would suggest to initially leave the controller on the module and use the connector mentioned to run straight to the battery.If you choose to move the controller or parallel to one controller, you will have a baseline from the original.
IMO, the Renogy would deliver about the same wattage with controller on the module or installed close to the batteries (at 10'-15' distance). I wouldn't install the suitcase into a paralleled MPPT controller. Unless you're real lucky, the controller will be confused, AKA loss of harvest.
RJfishin has a cute portable mount that he uses, attached to a receiver, IIRC. One or two wooden sticks will work, too. If I went with a portable on the ground, I think I'd be looking for something like an articulated television mount on an upright. I'd have it possible to be quickly mounted at one end of the RV.
