Your 'basic' load on the camper is 35 amp hours a day to run the refrigerator, CO detector and propane leak detector. This is about what your 100 watt solar panel will make on a good day. So don't be to surprised if the solar barely keeps up with the loads placed on it.
Yes the second panel will come in handy to keep it full. Yet even the 100 watt system will keep the battery full all the time if you have the Propane detector off, and refrigerator off. This really helps out and keeps the battery at it's full amp hour rating all it's lifetime. .
Fred.