One of the fields in my data is the form "lastname,firstname". Splunk extracts the last name and moves on to the next field when it reaches the comma. I have tried to create a regex that seems to work in the online regex tester I use, but does not work in my rex clause.
Your rex command doesn't put the matching text into a field so there's nothing in your table. The following rex command puts everything between 'CallerName=' and the following ';' into a field called 'name'.
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