What is causing Views to consistently but intermittently not find a view provided by the Advanced Forum module?
It sounds like you found the right answer from the IRC.  "Consistently intermittent" in my experience is when there are two sources filling the cache.  Most common is when you have a development site and a staging/production site on different code bases but same database.  The drupal-provided caches that I have read code for connect to the database, so routing/function information that is cached will cross contaminate.  Hitting the admin/modules page will refresh the module cache and locations, hitting the admin/views listing page clears your error because it refreshes the site's understanding of views from the perspective of your site instead of the perspective of whatever is conflicting with you.  

If you have server admin ability, change the password to your site's database and the password in your settings.php, and see what breaks.  Your listings should stop being corrupted and what is tampering with them should break ... unless it is directly connected to your site and using your settings.php file.

Also, check to make sure there are not multiple installations of the views module in your docroot.