FID values are only available in a TickHistoryRawExtractionRequest.
I have just checked the accepted ReportDateRangeType for this extraction, only Range, Relative, and DaysAgo are accepted. These all boil down to a range of data, so it seems that it is not possible to request only the last value.
You can use the ElektronTimeseriesExtractionRequest which provides historical Elektron end of day prices.
For more information, please refer to the REST API Tutorial 7: On Demand End of Day extraction tutorial.