Waterpump won't pull antifreeze out of bottle

Sounds like perhaps the pump is sucking air, or perhaps a vacuum. There are (logically) two valves that need to be changed: one connecting the pump inlet to the tank (which needs to be closed), and one connecting it to the suction hose (which should be opened). While it's certainly possible these could be combined in a single diverter valve, check that you aren't missing a valve you need to open or close.

RV water pumps are generally designed to be self-priming, at least with moderate suction lifts.