Problem using comma as field seperator in csv file

We use the Report Execution Service to run a report which is sent to a third party that uses the report to send out surveys.

With this functionality we are able to execute a report from outside CRM, specify the output format (xlsx, csv, txt, e-mail, etc.) and output location.

We have specified that the output of this report should be a .csv file which is placed on a location on one of our servers, where it is picked up by a File Handler which copies the file to a location on the third party's server.

The output contains a comma as the field separator and this is where we run into a challenge.