What area of the country are you from?
You sound like you’re worried about the roofer filing a lawsuit. I would be a lot more afraid of a lawsuit were I the roofer. Contracts cannot be ambiguous. The type of contract you are describing has been found to be unenforceable in court many times. Too ambiguous. It would be insurance fraud for them to charge you for work they didn’t perform as well.
I think you should be focused on getting your $40K plus roof fixed properly. That is a beautiful shingle but it also needs a more talented roofer to install it. Sounds like you had the misfortune of having an under talented roofer install it. If that is a local roofing contractor, you may very well have justification for taking them to court for a new roof.
You should be consulting your attorney at this point. If you want to send it to me, I’ll be happy to look the contract over for you and point out the problems it likely has. Assuming what you have described is mostly accurate, I don’t believe you have any legal ramifications to fear from the roofer.