I've been using iodophor for many years. I make sure all surfaces come into contact with it for one minute, then drain and invert the fermenter so residual liquid can trickle out. At this point, the water is just a thin film, and any remaining iodine should volatilize pretty quickly--which is the reason for that recommendation, to get rid of any remaining iodine. But you definitely do not have to wait for it to be dry for this; minutes will do (unless the water is ice cold or something).