Thank you for your time and patience throughout this issue! I reached out to our AKV SMEs and will post their update below.
When it comes to the backup/restore operation not working, this could be because - When you back up a key vault object, such as a secret, key, or certificate, the backup operation will download the object as an encrypted blob. This blob can't be decrypted outside of Azure. To get usable data from this blob, you must restore the blob into a key vault within the same Azure subscription and Azure geography. For more info - Design considerations
The version change is expected as you're creating new secrets hence new GUIDs. This will only affect the caller (ADF) if it has references using the secret's versions specific GUIDs, but if it's using just the name as reference then there should be no issues.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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