New 2025 23MLE. Is there a separate gravity fill for the fresh tank, other than the hose connection on the passthrough panel? I'm trying to sanitize, so attempting to pour a gallon or two into the fill inlet in the wet bay, even after rigging up something that screws into it, doesn't work - can't just pour water in. There is a Tank Vent driver's side near back of trailer, with a cover that is sealed to the wall with silicone: I saw a youtube of a Montana (
) that said just pop the cover off and that's the fresh fill? Is this true before I bust a seal?