I don't have any ideas as far as where the water is coming from. But from experience I know that if your carpet and the matting underneath is soaked, it will NEVER dry out unless you take it loose and get some air on it. It has no place for the water to go, and the foam pad underneath really sucks water up. It will begin to mildew and stink not long after it's soaked. Best bet is to remove the seat and the sill trim and elevate the carpet and matting then secure it somehow. Then place a small fan in there and leave it for a few days moving it around every so often. I hope you don't have to deal with this.