My RV also has a gray water dump valve for the kitchen plus a combined dump for the bathroom gray/black tanks. You really have 3 options, either find a "Y" hose connection, simply move the dump hose, or purchase another hose so you can move/switch the appropriate 90 degree clear end into the campground sewer when dumping.
Days camping (2016)----181 days
Days camping (2017) --- 82 days
2016 Wildcat MAXX 28RKX (33' TT), 2007 13' Scamp
2015 Ram Laramie Hemi, w/air suspension
30 years RV'ing
11 different RV's