Hi Jamie,
Thanks for bumping this thread. Since this thread was from a while back, I would have to check with the rest of our team whether there had been any updates regarding the issue.
Moving forward to yours, could you provide your the complete SOAP request and response logs that were generated when you uploaded your audiences and also, the complete Google Ads UI screenshot containing the similar error you encountered as stated in the original post?
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Best regards,
Peter
Google Ads API Team

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