Water leak on kitchen slide out after putting new seal on.

I previously had some questions about replacing a bunk end due to water damage. We are on a waiting list to get that repaired by a local dealer. Now there is a water leak over the kitchen slide out. My husband just replaced the seal, but still has a little leak. The damage from the water leak penetrated the wall over the stove, sink, couch and caused the wallpaper to bubble up quite a bit. Our neighbor said he had the same thing with a different trailer and did the repair himself by taking off the paper, sanding down the bubbles (craters),sealing the area and recovered the wallpaper to somewhat match. Has anyone done this and had it look decent? We hate to throw more money into it considering the cost of the new bunk end door. Thanks for your help.