Jim, it does. The vacuum break and check valve "should" drain one side to the outside and the other to the black tank.
I winterize it with RV Anti-freeze in case any water gets trapped in that valve.
Mine would be a bear to change (located in the rear corner of the toilet vanity) and the check valve in the gray tank flush is cheap plastic and the hose has a slight sag in it and could trap water.
Lou, Laura, & Freya the wonder dog
2008 GMC Sierra 3000HD Crewcab SB Allison Duramax
2019 Flagstaff 8529FLS - Pullrite 3300
HAM CALLSIGN - KC3FFW
Our Camco turbos worked perfect for six years in our previous TT, and I'll be using them in our new 320RS. We have one that came with our new TT and it is poorly located and does almost no good. The new trailer is somewhat of a bugger to get it to run clear on the outlet. The old trailer seemed to flow clean after just a couple cycles. The new one takes five to six times to get the same clean flow. I've been very pleased with the turbo flows.