I actually had an external integration beak because someone's last name contained "null". The integration failed with an invalid JSON error. After debugging the payload with one of their developers, we narrowed it down to one record. Apparently, they had a hardcoded rule where they replaced null with "" and it caused two double quotes on the property :|. I had to filter out this one record for a couple weeks until they received all of the approvals to push their fix to prod...
Ha. Had similar once. We were running a site hosted by “mega corp” and filtering results was just broken on live. After a protracted series of forms to get error logs I realised they were silently striping the “select” from the selection_id url param.
