Can I specify the Report Server URL in the Web API controller?
Yes. You can specify the reportServerUrl property for the Bold Reports® Report Viewer in the Web API controller, in the OnInitReportOptions method, as in the following code snippet:
[NonAction]
public void OnInitReportOptions(ReportViewerOptions reportOption)
{
reportOption.ReportModel.ReportServerUrl = "https://testing.SSRS.Server.com";
}