Querying time data in ArcGIS Maps SDK for .NET does not return the results of the query. Performing the same query the REST endpoint does provide results.
The team is unable to reproduce the issue with the latest versions of the SDK, ArcGIS Runtime SDK 100.15.3, and ArcGIS Maps SDK for .NET 2003. If users have any questions or need further assistance on this issue, please reach out to Esri Technical Support.