Weather Queries: Packing For Phong Nha Rain

I’m visiting during the shoulder rainy season in Phong Nha-what should I pack to stay comfortable? Should I bring a heavy raincoat or just a light poncho? Are waterproof hiking shoes necessary, or will rubber sandals suffice on muddy trails? Do guesthouses provide towel drying services, or should I bring extra towels? Any advice on preventing gear from getting soaked when trekking between caves?