Find a service center that has a SealTech machine which will expose all the potential leaks. Testing costs about 2 maybe 3 labor hours. Once you know where the leak is stopping further water intrusion is easy. With a bit of luck there water damage isn't much and you don't get a delamination bubble in the sidewall.
https://rvleaks.com/
If you're a DIY type person I've seen Youtube videos of owners who build a tester using leaf blowers to build up pressure in the coach for soap bubble testing.
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