After experimenting for a long time, I noticed that the issue was with the trailing slash at the end of the URL.
https://it.blogs.unr.edu/outages – redirect error
https://it.blogs.unr.edu/outages/ – loaded the page fine.
I also confirmed that this was the case for entering the URL of any page in any of the multisite sites.
When I entered in the url with no trailing slash, a trailing slash was added to the URL. However, I reckon that the browser cache still refused to redirect the page properly.
So, I added the following to the .htaccess file, and that appears to have fixed the problem:
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.*[^/])$ /$1/ [L,R=301]
Basically, this code takes any URL not ending with a slash, and redirects them to the URL with the slash.
