Could they win? I don't think it matters.
This is the primary argument in favour of copyright paranoia. Is our position based on principles or on fear? If our only argument is fear of successful litigation, what is that but paranoia? I don't think we should simply take on issues solely for the purpose of setting up litigation; we should show some care in choosing our battles. Principled positions give us more flexibility.
What is called copyright paranoia comes in many forms, and I see this one as the least legitimate one. One form of copyright problems is having dubious copyright text interspersed in an article. I think this is the worst one, because it can so easily taint the entire article and even spread to other parts of the encyclopedia through copy and paste. It's also the easiest to fix, because text of this sort can easily be rewritten. Then there are dubious claims of fair use in the encyclopedia, in ways that are easily removed (especially images, but also quotes, song lyrics, etc). This isn't really a legal problem for Wikipedia, it's a problem for those who might want to reuse the encyclopedia, and therefore a problem with the free status of the encyclopedia.
Finally, there's what we're seeing here, a copyright problem in a side-page which isn't even in the encyclopedia itself. For another example, consider a fair use image being used on someone's user page. Assuming this doesn't taint the actual encyclopedia, there really isn't much of a problem at all.
Now yes, this all rests on the assumption that having a list in the Wikipedia space doesn't taint any of the article space. But I haven't heard any educated arguments that this assumption is invalid.
Anthony