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Happy to answer your questions.
Thanks for your query. Could you please try registering a different supported data source by ADC? - This is just to narrow down the root cause analysis.
If you are not able to see any registered objects ( using registration tool) in ADC, I would suggest you to try registering the objects from a different machine (try with personal machine) and check if you were able to see those objects registered in ADC. The reason behind this is that I have seen cases where user(s) had similar issue due to Endpoint protection software installed on their business machine to protect their business network. If that was the root cause, you might need to disable such software.
Hope this helps.