I'm not seeing anything in my nginx error log when this happens.
Also sometimes I get this error instead of the previous one I mentioned: "Search result already expired, please try a new search." This error doesn't take up the whole screen, where the first error I mentioned in my first post did take up the whole screen and didn't render any images/styles/themes.
Here is the actual website:
https://graal.in/
I'll leave the slave database enabled for a while.