Yup, it the galley grey water tank dump handle. Not in the most convenient place but still there.
I use my awning rod to pull and close it and I don't have to go under the slide to get to it then. At least that is where mine in located is half way down the long slide out. I think they changed it some on later models but now they are all in the service center, I THINK!!!
But who knows for sure!
UPDATE FROM FIRST POST---Well I guess I was wrong according to jlb27537. Looks like Keystone has not changed the galley tank drain handle yet. I had assumed all three tank drain handles were put into the convenient center. May have to keep my awning rod INCASE I can talk the DW into a new unit!