Why does the passenger side floorboard Get wet?
If the dampness is coolant,then you have a leaking heater matrix.
If it's towards the firewall on the passenger side floor, I'm going to assume that you either have had your windshield replaced recently or, you need it replaced. Either way, most "wet floors" in vehicles are do to poor windshield installation (not sealing properly) or a crack in the glass that may or may not be visible. You would smell coolant for sure if it were that.
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