... not exactly the same RV, but I had he same issue with my trailer. I sent a picture to Winnebago CS, but never heard back from them (didn't expect to).
You can see by the stock part that was removed, the port on the fresh water tank has 1/2" pipe threads. That offers you some options.
My solution was a PVC run nearer to the side of the trailer. I can easily reach the valve through the stairwell. The fitting on the valve end has garden hose threads so I can direct the water away from the trailer. ... simple and inexpensive.
The original drain could have easily been mounted to the trailer frame. It would have needed a couple of feet more of braided tubing and two screws - less than $5. (I wonder if someone that is about 6' 9" tall, has a 38" reach, and never camped before got a bonus for this cost saving design.)
Edit: I used threaded fittings on the PVC run so it would be easier to replace or repair if it was damaged from something kicked up from the road.