2019 Kodiak water in wheel well

Have you checked the roof? Water can leak in at the roof, find its way into the laminated wall panel between the foam and luan, and come out at the bottom of the panel. Your picture seems to have some yellow material that may be the water based adhesive leaching out if the above is happening although the adhesive is typically red.

Just about every trailer made has the same plastic fender skirt such as your Kodiak installed the same exact way. Re caulk the top of in and remove, back caulk, and reinstall the screws.