Hi I am new to Renegade and I'm having this very same issue with my 2020 Veracruz that I just picked up a few days ago. I went to drain the tank (via the valve located under the bed) and it won't drain. It's just a slight dribble. There is a LOW POINT drain valve in the water compartment, but that does nothing to drain the tank. I'm waiting to hear back from the North Trail RV service center, but they are puzzled too.
The low point drain that's located in the water closet has a small white tip sticking out of it. It won't drain any water until I pull on the white tip with a pair of pliers. Then it releases the residual water.
Any help would be appreciated.