Wiki ignores case looking up pages. It finds pages based on a "slug" that consists of lower-case and dashes. The page creation logic goes to some effort to discover what capitalization was intended and stores that with the page.
Aside: Rather than 404 Page Not Found this wiki returns a ghost page with a 'future' plugin that offers to make or find the page by a variety of mechanisms. The preferred title is fetched by finding the citation in the dom and pulling the title out of it. github 
If you don't like the title capitalization you have now you can use what ever capitalization you prefer when citing a page.
If you don't like the title capitalization as it appears on the page then you're stuck for the moment.
It doesn't have to be this way. A double-click of the title should let you change capitalization in place. A spelling change should work too, leaving the old version in place to direct bad spellers to the better. This is how wiki should work but for now, capitalization sticks.