Using dynamic defaults with QuickSight and Terraform

Hello, I try to implement the dynamic defaults feature of QuickSight (see Parameters default values) using Terraform.

This is an extract of the relevant .tf file:

...
parameter_declarations {
      string_parameter_declaration {
        name                 = "ReportDatetimeParameter"
        parameter_value_type = "SINGLE_VALUED"
        default_values {
          dynamic_value {        
            user_name_column {
              data_set_identifier = aws_quicksight_data_set.qs_dynamic_defaults_dataset.id
              column_name         = "Username"
            }
            default_value_column {
              data_set_identifier = aws_quicksight_data_set.qs_dynamic_defaults_dataset.id
              column_name         = "Default value"
            }
          }
        }
      }
    }
...

However, when I apply this, I get back the error that at least 1 group_name_column block is needed, although the documentation of Quicksight clearly says that this parameter is not required (see API).

Any ideas how to tell the API that I want to use only username for the dynamic default? In the console, you have the possibility to select None: