Hello, Dominik,  

As it is noted in the online documentation, due to performance considerations and in order to decrease the consumed memory the visual settings and view definitions in RadGridView are not exported when the operation is run async. If you need to export visual settings feel free to run the export synchronously by using the RunExport method.

I hope this information helps. If you need any further assistance please don't hesitate to contact me. 

Regards,
Dess
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