Your 2015 Subaru Forester:
Towing1. Release the parking brake and put the transmission in the N /neutral position.2. The ignition switch should be in the ACC position while the vehicle is being towed.3. Take up slack in the towline slowly to prevent damage to the vehicle
For CVT models, the traveling speed must be limited to less than 20 mph (30 km/h) and the traveling distance to less than 31 miles (50 km). For greater speeds and distances, transport your vehicle on a flat-bed truck
I think this is pretty clear, your speed is limited to 20 mph and for no more than 31 miles. Won't work as a Toad for an RV. Get a car carrier and then you'll be OK.