Is it actually worth it to try and sue the previous owners for not disclosing water damage?

For context, we bought our house late July, owners stated there was no history of water damage. Last week during a rain storm our ceiling on the first floor started leaking. On the second floor we found the leak in a crawl space where the insulation had fallen off and there was clearly cardboard put here to prevent water from getting below. We had a roof repairman out today and he looked at the roof and took pictures of what he deemed clearly was a shoddy patch job, he could see the caulking that was used to try and keep the shingles together. He said it looks like the water has been getting in the last 2 months at least, it just took longer to become noticeable because it had to make its way down to the first floor, most likely because of the cardboard put there by someone before we bought the house. The house inspector also didn’t catch any of this which is also frustrating.

So I guess my question is, is this worth pursuing? Is the roofer’s testimony actually enough to prove they knew about this issue? We are getting quoted about 12k because the entire roof would need to be replaced, and he estimated the roof is about 15 years old. We will be looking through the paperwork to find out what the owners stated on when it was last replaced. If this is worth pursuing, how long does this process actually take?