@Janne Kujanpää Welcome to Microsoft Q&A a Forum, Thank you for posting your query here!
Customer-managed key is delivered on dedicated clusters providing higher protection level and control. Data to dedicated clusters is encrypted twice, once at the service level using Microsoft-managed keys or Customer-managed keys, and once at the infrastructure level, using two different encryption algorithms and two different keys.
For Customer-managed key for saved queries and log alerts you can view through query language in Log Analytics.
If we regenerate the access keys manually, that gets logged in the Activity Logs. The one you're mentioning here is about encryption keys in the scenario you can use Azure Monitor
This article provides detailed information on Azure Monitor customer-managed key
Please let us know if you have any further queries. I**’m happy to assist you further.**
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