That is not quite my issue, I understand that the comma is used to separate the fields that I want to use.
My problem is that one of the Field values I want to use as a parameter has a comma: Sales / Observe, Listen
In order to be able to use the variable correctly I need to find a way to have $(QuestionType(2, Sales / Observe, Listen)), in a way that the comma between Observe, Listen is assumed as part of the value and not a separator of the parameters.
It's a long running problem/limitation that you can't use a comma in the variable parameter value. It's always interpreted as a parm separator. The only workaround I've found is to use a proxy character as Felip suggested.