insurance trying to screw meeeeeee

They will cover leak damage if it's somewhere that you could not have reasonably seen. If you should have seen it and fixed it before it caused damage then it's on you. I have had one such as that covered in the past. The leak was from a running light in the back. There was no indication in the coach until brown water started leaking out from under the inside wall at floor level. I took it to get fixed and when they opened it up the whole rear wall was basically destroyed. Allstate covered it without question. It all depends on the circumstances.