You really do not know the extent of the damage until you get the interior wall panels pulled apart. Looking at the photos, I would think that you will find severe structural damage. I think that the Rockwood trailers are wood-framed, so at least this can be rebuilt without metal working skills.
More than likely, the slide will have to come out of the trailer, and this is generally a shop procedure. I would throw out a guess that to get this repaired, you are looking at something in the range of $5,000.
You have to decide if it is worth the money to repair this.
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