Good to read that you got it sorted! And I agree with aooga, call Samsung and be decisive, ask for a higher tier when they say they can't help you. Usually you will get good service when you politely push a bit. Your issue now is that your phone still isn't waterproof, so you can tell them that is your warranty issue, phone does not comply with IP67 as advertised.
They of course can test that their selves, put in a new sticker that can detect water, close every port and all that, put it in water and see what happens. If in that case the stickers got tripped again, they have to solve your problem under warranty.