I have not yet encountered any issues between the Hub 3.0 and RDP but I will look into this for you and do my best to help get this sorted.
I am aware that the passthrough options on the Hub 3.0's are not yet working correctly, Making a logical guess, it's possible that this is the cause of your issues. This will be addressed in a future firmware update.
In the meantime, you can have a look at this Microsoft support page, hopefully there'll some information that can help you.
Alternatively, perhaps you could consider using your Hub 1, until the passthrough options function correctly in the Hub 3.0.
I look forward to your reply,
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