Sorry to hear about your misfortune. But your experience is not wholly uncommon. It happens sometimes. Fortunately, your car appears to be in good shape with no rust to begin with. Pulling the carpets and seats and letting everything dry out should solve the problem. Fans and/or a bucket full of desiccant material (either silica gel or calcium chloride like DampRid) should help also. I recently replaced that non-woven insulation under the ECU with a thick rubber sheet cut to size for exactly this reason. I didn't want something that could trap moisture and promote mold growth or corrosion.