How to test server side fingerprint?

I have the following test cases that happened with me:
https://sentry.io/share/issue/b5744714108b4006a7aed840d3e13aa8/
and
https://sentry.io/share/issue/79e3c72b0da2477eb87acdad95faa9bf/

I would like to group all events where the exception value doesn’t start with
{"Codigo":"InternalServerError","Mensagem":"

But it’s really bad to test this case due to the quotation marks symbols in the string and having to send a new event to check if it’s filtering correctly.

So my questions are, is there an easy way for testing the server side fingerprint that I made using an existing event ? (to see if it’s going to work or not)
Does server side fingerprint supports not operation? like if a exception doesn’t contain ‘aaa’, but ‘bbb’ group to fingerbbb.