I think this is a massive issue for both of you and I don't know how we can resolve it. Because it's an issue for you because you don't have time to work on it and you can't always work for free. But most people are on the other side. They work for a company and the company want them to use a package. But the package doesn't work or doesn't have the feature they need. The can't fix it or add the feature because their…
Certainly this sounds like an issue for you and your company, but I don't see why it is an issue for the project and its maintainers. Many companies enter into support contracts with vendors whose solutions they adopt to avoid this very problem. The solution seems simple to me, your company should seek a support contract with the vendor, and if that is not possible, find a different solution for which they can. It is…
Don't forget you are here on HN with HN developers. 99% of companies will never seek support contract with vendors. That's the reality, developers have to deal with it and get over the struggle. Maintainer have to deal with it too because companies will never change (or at least not in the few months) and get over developers asking for help which have issues with their library.