You should have a sewer cleanout/access somewhere around the house--find it. Then get a FloJet macerator pump that attaches to the sewer drain and use a water hose to pump waste over to the sewer access. Should be good for over 100' if not 10' up-elevation difference. Then you can use the trailer facilities as you like and dump thru the macerator pump. I did this for 3 months while house was remodeled, works a lot better than going over to the house at night....
2016 Tiffin 40 QBH
2015 38RSSA, traded
2005 TK3 #1869, 10 yrs of memories,
2017 F450 KR--one more Ford is it
2009 F450 4x4-died; 2010 F450-retired