BAQReports need a filter (XML) with the filters to be supplied. Like this
var rptDs = dynamicReport.GetByID("EDI870EXPORT");
var baqRptDS = baqR.GetNewBAQReportParam("EDI870EXPORT");
baqRptDS.BAQReportParam[0].Option01 = guid.ToString();
baqRptDS.BAQReportParam[0].AutoAction="SSRSGenerate";
baqRptDS.BAQReportParam[0].SSRSRenderFormat = "CSV";
baqRptDS.BAQReportParam[0].Character01=guid.ToString();
baqRptDS.BAQReportParam[0].Character02=flag;
baqRptDS.BAQReportParam[0].BAQRptID="EDI870EXPORT";
baqRptDS.BAQReportParam[0].ReportID="EDI870EXPORT";
baqRptDS.BAQReportParam[0].Summary = false;
baqRptDS.BAQReportParam[0].ReportStyleNum = 1002;
baqRptDS.BAQReportParam[0].BAQID="FAM-EDI870-DASHBOARD";
baqRptDS.BAQReportParam[0].ReportTitle = "EDI 870 Export";
baqRptDS.BAQReportParam[0].TaskNote = guid.ToString();
rptDs.BAQRptOptionFld[0].FieldValue = guid.ToString();
rptDs.AcceptChanges();
StringWriter writer = new StringWriter();
rptDs.WriteXml(writer);
baqRptDS.BAQReportParam[0].Filter1 = writer.ToString();