does it have rv parking?

Yes

Yes, Dollywood had RV parking. Oversize length vehicles $18 for parking. River's Edge and Clabough's Campground are popular and on the trolley route.

Yes it does.

Yes. They do. "Parking for RVs and oversize vehicles is $18. This allows you to park your RV in our "Permit Parking" lot. Trams provide transportation to the Front Gate. RV parking lot is not available for overnight parking or camping." That is as of November 2017. I'm sure that price is subject to change.

Yes, I believe they do. Call there customer service number to be sure.