I feel your pain, and we go through this every year with our 2014 Parkliner which may be slightly different from yours.
First off parallel=ON and perpendicular-Off. once we have drained our fresh water tank (we have one) then we drain the hot water tank and after turn on the bypass valve.
We add a gallon of RV antifreeze and then flip the water pump switch which is to the upper right of the sink and stove area. We allow the pink stuff to come out of the sink faucets, the shower head faucets and turn off all the faucets. we add antifreeze to the toilet, flush, add some more, flush and then add some to the drain in the floor and push the shower drain button so it goes down a couple of times. It is probably overkill but I also wrap a moving blanket or insulation around the fresh water tank for extra insulation. If you have any questions I hope you will message me. Good luck and I know how frustrating this is to figure out. PJ