Thank you for writing.
I would like to note that when you setup grid hierarchy, you add a template which is common for the entire child level. Hence, it uses common columns. However, in order to achieve your goal, you can add several child templates and display the relevant one (and hide the other/s) when expanding a master row. A sample approach is demonstrated in our Formatting Cells help article >> Example 4: Hiding child tabs when no data is available section
I hope this information helps. Should you have further questions, I would be glad to help.
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