We have had a leak in our rear bedroom slide off and on for a while that appears at the outside floor of HR Vacationer motorhome. We have checked roof and it looks fine. seals look fine. We have now noticed that when the slide is extended out that on the bottom outisde the bottom seems to be drooping down from the edge and it appears this may be how the water is seeping in. We tried silicone to seal, but did not hold. Any suggestions on what to use to seal this outisde portion back in place and fix the leak?