Shiny app crashes loading some layers in Leaflet map, but only when deployed. No errors in logs

Hi -
I am having a hard time troubleshooting a problem with a Shiny app deployed to You can see it here:
The app works fine locally, but crashes when loading certain layers when deployed on You can see by selecting "Buildings_2014" then "Load Building Layer". It takes a little while, but it will crash. Nothing shows up in the log, but using the inspector the problem seems to be a 500 - Internal Server Error

I don't know how to troubleshoot this one. It was also giving errors in the browser console related to fonts and javascript files it couldn't find, so I removed the bslib theme I was using, but that hasn't fixed it. Any leads appreciated.