Often, the people who find a bug are the ones who try to fix it. And each contributor has a personal reason for being on the project. If I can get that working, my wife and I would be quite happy to never boot Windows again. The Wine project is also caught up in the breakup of Microsoft ordered by Judge Thomas Penfield Jackson. One proposed remedy for the case would force Microsoft to make its source code and APIs available to competitors that want to ensure compatibility.
Wine is one such group.
And it would remove the need to illegally reverse-engineer parts of Windows to get the answer. Complete, open and honest documentation would help us. But no one seems to think this help will come soon. The Wine group isn't waiting, in part because it wants to write cleaner software. It gets the benefit of hindsight when programmers clone the architecture, and this makes it much easier to create something better.