it’s not at all a wiki based solution, but i once created a sample for creating a help system (actually i just updated it today). You can have a look at it here:
Basically it is an Entity (ContextHelp) that you can use for creating content. Obviously since CUBA has already user management either anyone or just a subset of the users are allowed to edit the help content.
If you want to have further information, you can check out the README.md on the project.
Besides the end result, this does not really have anything to do with a wiki, it does not support wiki syntax etc. Regarding tracability, you could use CUBAs entity log or entity snapshots feature to enable a similar result.
I hope this helps.