You have highlighted a particularly hard to solve issue - where an error is thrown in an asynchronous callback the user has created without any proper error handling. We cannot add error handling for that because it isn't our code.
In your code you know when the server crashes
4 Sep 08:22:55 - [red] Uncaught Exception: 4 Sep 08:22:55 - ReferenceError: undefindenFunction is not defined at Function node:cdf5d431.98a838 [Camera Init]:14:5 nodered.service: Main process exited, code=exited, status=1/FAILURE
however a new user mite be confused by the message "This site can’t be reached"
instead of leaving the user in mid air with a dead server you can redirect to a page that tels the user what happened and present him with some options