The difference between the scenario described in the How to: Create a Master-Detail Report Using a SubReport Item
article and your case is that you will use TRDX files, and UriReportSource
The way you pass values between the master and sub reports is correct. If the sub report data must be filtered based on the report parameter, please double-check if you have set the filter expression properly on the right data item
If you need any further help, feel free to open a support ticket and send us the report files, including test data to check the settings.
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