Logs show missing files, but they appear to exist

Two issues that appear to be related.

  1. Every so often I get a server error that I am unable to access the site. Refreshing the page fixes this, but it is very annoying.
  2. Sometimes the page formatting is missing a lot of details, and just throws all the lines on top of each other with missing images and backgrounds.

I have two screenshots attached, let me know what other information I can provide. The way this is configured is two Linux VMs behind a load balancer with sticky connections. Web site files are stored on an NFS share that both instances have access to. They use a redis caching server for file locking and memory caching. However, the actual shared storage is on a SAMBA shared and accessed via external storage. I have no issues with that part of things.

The server shows missing files, but when I check the server filesystem I see the files mentioned. I am assuming PHP is looking for something that I am missing.

UPDATE:
Here is the log from when I had the formatting issue just now.

{“reqId”:“YABaz4nPlmFtsIvMc0S0@gAAAFg”,“level”:2,“time”:“2021-01-14T14:53:15+00:00”,“remoteAddr”:“192.168.20.47”,“user”:“6B8BE64D-431F-4423-BC45-8F9C2BCABEA0”,“app”:“core”,“method”:“GET”,“url”:"/settings/admin",“message”:“Failed to compile and/or save /var/www/html/nextcloud/core/css/server.scss”,“userAgent”:“Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.88 Safari/537.36”,“version”:“20.0.4.0”,“id”:“60006812f3d3b”}

I am thinking of copying the standard web files to each instance, then mounting any shares and log directories dynamically. My theory is that one instance is maybe locking the files while the other server tries to access. But that’s just a theory.