The best way to allow multi-user access seems like it would be a data folder synced to a git repo. This would not work perfectly but it should work well.
Having an index autogenerated as a build step somehow would also work.
Seems like there should be a way to host the wiki on GitHub.io and allow a static wiki to pull in the latest version from the repo so people can read it. Probably something along the lines of loading the tiddlers from the repo and then calling boot after it's done.
Just a random idea that should work. TiddlyWiki teases me with its endless possibilities.