Assignment

I would take a look at what plugins the teacher is using and maybe try disabling them one at a time. Also, do you have another server that might also be caching? Have you also cleared browser caches? When I am trying to troubleshoot, I tend to manually delete the cache and localcache folders from the moodleDATA folder (not the code folder). And then clear the browser caches. You might see if chrome developer tools tools shows anything being blocked on the page...